Service Manualmidea.com.ge/uploads/client/Uploads/Catalogues/Service... · 2018. 12. 19. · Midea...

Commercial Air Conditioners

R410A

Series

MV6-252WV2GN1-E

MV6-280WV2GN1-E

MV6-335WV2GN1-E

MV6-400WV2GN1-E

MV6-450WV2GN1-E

MV6-500WV2GN1-E

MV6-560WV2GN1-E

MV6-615WV2GN1-E

MV6-670WV2GN1-E

MV6-730WV2GN1-E

MV6-785WV2GN1-E

MV6-850WV2GN1-E

MV6-900WV2GN1-E

Service

Manual

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NTEN

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CONTENTS

Part 1 General Information ............................................................................ 3

Part 2 Component Layout and Refrigerant Circuits ................................... 11

Part 3 Control ............................................................................................... 33

Part 4 Field Settings ..................................................................................... 49

Part 5 Electrical Components and Wiring Diagrams .................................. 55

Part 6 Diagnosis and Troubleshooting ......................................................... 69

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Part 1

General Information

1 Indoor and Outdoor Unit Capacities .................................................. 4

2 External Appearance ............................................................................ 6

3 Outdoor Unit Combinations ................................................................ 8

4 Combination Ratio ............................................................................... 9

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1 Indoor and Outdoor Unit Capacities

1.1 Indoor Units

1.1.1 Standard indoor units

Table 1-1.1: Standard indoor unit abbreviation codes

Abbreviation

code Type

Abbreviation

code Type

Q1 One-way Cassette T1 High Static Pressure Duct

Q2 Two-way Cassette G Wall-mounted

Q4C Compact Four-way Cassette DL Ceiling & Floor

Q4 Four-way Cassette F Floor Standing

T2 Medium Static Pressure Duct Z Console

Table 1-1.2: Standard indoor unit capacity range

Capacity Capacity

index Q1 Q2 Q4C Q4 T2 T1 G DL F Z

kW HP

1.8 0.6 18 18 — — — — — — — 18 —

2.2 0.8 22 22 22 22 — 22 — 22 — 22 22

2.8 1 28 28 28 28 28 28 — 28 — 28 28

3.6 1.25 36 36 36 36 36 36 — 36 36 36 36

4.5 1.6 45 45 45 45 45 45 — 45 45 45 45

5.6 2 56 56 56 — 56 56 — 56 56 56 —

7.1 2.5 71 71 71 — 71 71 71 71 71 71 —

8.0 3 80 — — — 80 80 80 80 80 80 —

9.0 3.2 90 — — — 90 90 90 90 90 90 —

10.0 3.6 100 — — — 100 — — — — — —

11.2 4 112 — — — 112 112 112 — 112 — —

14.0 5 140 — — — 140 140 140 — 140 — —

16.0 6 160 — — — — — 160 — 160 — —

20.0 7 200 — — — — — 200 — — — —

25.0 9 250 — — — — — 250 — — — —

28.0 10 280 — — — — — 280 — — — —

40.0 14 400 — — — — — 400 — — — —

45.0 16 450 — — — — — 450 — — — —

56.0 20 560 — — — — — 560 — — — —

1.1.2 Fresh air processing unit

Table 1-1.3: Fresh air processing unit capacity range

Capacity 12.5kW 14kW 20kW 25kW 28kW

Capacity index 125 140 200 250 280

1.2 Heat recovery ventilator Table 1-1.4: Heat recovery ventilator capacity range

Capacity 200m3/h 300m

3/h 400m

3/h 500m

3/h 800m

3/h 1000m

3/h 1500m

3/h 2000m

3/h

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1.3 Outdoor Units Table 1-1.5: Outdoor unit capacity range

Capacity Model Name Combination Type

8HP MV6-252WV2GN1 /

10HP MV6-280WV2GN1 /












34HP MV6-950WV2GN1 12HP+22HP
















66HP MV6-1850WV2GN1 12HP+22HP+32HP
















Notes: 1. The combinations of units shown in the table are factory-recommended. Other combinations of units are also possible.

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2 External Appearance

2.1 Indoor Units

2.1.1 Standard indoor units

Table 1-2.1: Standard indoor unit appearance

One-way Cassette Two-way Cassette

Q1

Q2

Compact Four-way Cassette Four-way Cassette

Q4C

Q4

Medium Static Pressure Duct High Static Pressure Duct

T2

T1

Wall-mounted Ceiling & Floor

G

DL

Floor Standing Console

F

Z

2.1.2 Fresh air processing unit

Table 1-2.2: Fresh air processing unit appearance

Fresh Air Processing Unit

FA

2.2 Heat Recovery Ventilator Table 1-2.3: Heat recovery ventilator appearance

Heat Recovery Ventilator

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2.3 Outdoor Units

2.3.1 Single units

Table 1-2.4: Single outdoor unit appearance

8/10/12HP

(with single fan)

14/16HP

(with single fan)

18/20/22HP

(with dual fans)

24/26/28/30/32HP

(with dual fans)

2.3.2 Combinations of units

Table 1-2.5: Combination outdoor unit appearance

34HP 36/38HP 40HP

42/44HP 46/48/50HP 52/54/56/58/60/62/64HP

66HP 68/70HP 72HP

74/76HP 78/80/82HP 84/86/88/90/92/94/96HP

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3 Outdoor Unit Combinations

Table 1-3.1: Outdoor unit combinations

System capacity Number

of units

Modules1 Outdoor branch

joint kit2 kW HP 8 10 12 14 16 18 20 22 24 26 28 30 32

25.2 8 1

—

28.0 10 1

33.5 12 1

40.0 14 1

45.0 16 1

50.0 18 1

56.0 20 1

61.5 22 1

67.0 24 1

73.0 26 1

78.5 28 1

85.0 30 1

90.0 32 1

95.0 34 2

FQZHW-02N1E

101.5 36 2

106.5 38 2

112.0 40 2

117.5 42 2

123.0 44 2

128.5 46 2

134.5 48 2

140.0 50 2

146.0 52 2

151.5 54 2

157.0 56 2

163.5 58 2

168.5 60 2

175.0 62 2

180.0 64 2

185.0 66 3

FQZHW-03N1E

191.5 68 3

196.5 70 3

202.0 72 3

207.5 74 3

213.0 76 3

218.5 78 3

224.5 80 3

230.0 82 3

236.0 84 3

241.5 86 3

247.0 88 3

253.5 90 3

258.5 92 3

265.0 94 3

270.0 96 3

Notes:

1. The combinations of units shown in the table are factory-recommended. Other combinations of units are also possible. 2. For systems with two or more outdoor units, outdoor branch joints (sold separately) are required.

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4 Combination Ratio

Table 1-5.1: Indoor and outdoor unit combination ratio limitations

Type Minimum

combination ratio

Maximum combination ratio

Standard indoor units only

Fresh air processing units only

Fresh air processing units and standard indoor units together

V6 Series outdoor units 50% 130% 100% 100%1

Notes: 1. When fresh air processing units are installed together with standard indoor units, the total capacity of the fresh air processing units must not exceed 30%

of the total capacity of the outdoor units and the combination ratio must not exceed 100%.

Table 1-5.2: Combinations of Indoor and outdoor units

Outdoor unit capacity Sum of capacity indexes of connected indoor units (standard

indoor units only)

Sum of capacity indexes of connected indoor units (fresh air processing units and standard

indoor units together)

Maximum number of connected indoor

units kW HP

Capacity index

25.2 8 252 126 to 327.6 126 to 252 13 28.0 10 280 140 to 364 140 to 280 16 33.5 12 335 167.5 to 435.5 167.5 to 335 20 40.0 14 400 200 to 520 200 to 400 23 45.0 16 450 225 to 585 225 to 450 26 50.0 18 500 250 to 650 250 to 500 29 56.0 20 560 280 to 728 280 to 560 33 61.5 22 615 307.5 to 799.5 307.5 to 615 36 67.0 24 670 335 to 871 335 to 670 39 73.0 26 730 365 to 949 365 to 730 43 78.5 28 785 392.5 to 1020.5 392.5 to 785 46 85.0 30 850 425 to 1105 425 to 850 50 90.0 32 900 450 to 1170 450 to 900 53 95.0 34 950 475 to 1235 475 to 950 56

101.5 36 1015 507.5 to 1319.5 507.5 to 1015 59 106.5 38 1065 532.5 to 1384.5 532.5 to 1065 63 112.0 40 1120 560 to 1456 560 to 1120

64

117.5 42 1175 587.5 to 1527.5 587.5 to 1175 123.0 44 1230 615 to 1599 615 to 1230 128.5 46 1285 642.5 to 1670.5 642.5 to 1285 134.5 48 1345 672.5 to 1748.5 672.5 to 1345 140.0 50 1400 700 to 1820 700 to 1400 146.0 52 1460 730 to 1898 730 to 1460 151.5 54 1515 757.5 to 1969.5 757.5 to 1515 157.0 56 1570 785 to 2041 785 to 1570 163.5 58 1635 817.5 to 2125.5 817.5 to 1635 168.5 60 1685 842.5 to 2190.5 842.5 to 1685 175.0 62 1750 875 to 2275 875 to 1750 180.0 64 1800 900 to 2340 900 to 1800 185.0 66 1850 925 to 2405 925 to 1850 191.5 68 1915 957.5 to 2489.5 957.5 to 1915 196.5 70 1965 982.5 to 2554.5 982.5 to 1965 202.0 72 2020 1010 to 2626 1010 to 2020 207.5 74 2075 1037.5 to 2697.5 1037.5 to 2075 213.0 76 2130 1065 to 2769 1065 to 2130 218.5 78 2185 1092.5 to 2840.5 1092.5 to 2185 224.5 80 2245 1122.5 to 2918.5 1122.5 to 2245 230.0 82 2300 1150 to 2990 1150 to 2300 236.0 84 2360 1180 to 3068 1180 to 2360 241.5 86 2415 1207.5 to 3139.5 1207.5 to 2415 247.0 88 2470 1235 to 3211 1235 to 2470 253.5 90 2535 1267.5 to 3295.5 1267.5 to 2535 258.5 92 2585 1292.5 to 3360.5 1292.5 to 2585 265.0 94 2650 1325 to 3445 1325 to 2650 270.0 96 2700 1350 to 3510 1350 to 2700

Combination ratio = Sum of capacity indexes of the indoor units

Capacity index of the outdoor units

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Part 2

Component Layout and

Refrigerant Circuits

1 Layout of Functional Components ....................................................... 12

2 Piping Diagrams .................................................................................. 16

3 Refrigerant Flow Diagrams .................................................................. 22

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1 Layout of Functional Components

8/10/12HP Figure 2-1.1: 8/10/12 layout of functional components

Legend

No. Parts name

1 Compressor

2 Discharge temperature switch

3 High pressure switch

4 High pressure sensor

5 Oil separator

6 Four-way valve

7 Heat exchanger

8 Electronic expansion valve (EXV)

9 Low pressure switch

10 Fan motor

11 Fan

12 Stop valve (liquid side)

13 Stop valve (gas side)

14 Plate heat exchanger

1556

7

8

12 13 14

11

9

10

3 4 2 1

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14/16HP Figure 2-1.2: 14/16 layout of functional components

Legend

No. Parts name

1 Compressor




5 Oil separator

6 Four-way valve

7 Heat exchanger



10 Fan motor

11 Fan




15 Accumulator

1556

7

8

12 13 14

11

9

10

34 2 1

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18/20/22HP Figure 2-1.3: 18/20/22 layout of functional components

Legend

No. Parts name

1 Compressor




5 Oil separator

6 Four-way valve

7 Heat exchanger



10 Fan motor

11 Fan




15 Accumulator

1556

7

8

12 13 14

11

9

10

34 2 1

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24/26/28/30/32HP Figure 2-1.4: 24/26/28/30/32 layout of functional components

Legend

No. Parts name

1 Compressor




5 Oil separator

6 Four-way valve

7 Heat exchanger

8 Electronic expansion valve

(EXV)


10 Fan motor

11 Fan




15 Accumulator

155 46

7

8

9

12 13 14

11

9

10

3 2 1

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2 Piping Diagrams

8/10/12HP

Figure 2-2.1: 8/10/12HP piping diagram

Legend

No. Parts name

No. Parts name

1 Compressor 14 Plate heat exchanger

2 Discharge temperature switch 15 Accumulator

3 High pressure switch 16 Heat exchanger cooling electric control box

4 High pressure sensor T3 Heat exchanger temperature sensor

5 Oil separator T4 Outdoor ambient temperature sensor

6 Four-way valve T6A Plate heat exchanger inlet temperature sensor

7 Heat exchanger T6B Plate heat exchanger outlet temperature sensor

8 Electronic expansion valve (EXV) T7C1 Compressor A discharge temperature sensor

9 Low pressure switch T7C2 Compressor B discharge temperature sensor

10 Fan motor SV4 Oil return valve

11 Fan SV5 Fast defrosting (in heating) and unloading (in cooling) valve

12 Stop valve (liquid side) SV6 Refrigerant bypass EXV valve

13 Stop valve (gas side) SV8A Compressor A vapor injection valve

7

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3

2

45

6

1110

9

14

8

8

13

EXVA

EXVC

E SC

T3

T4

T6B

T7C1

T7C

2

T6A

SV8A SV

4

SV5

SV6

16

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14/16HP

Figure 2-2.2: 14/16HP piping diagram

Legend

No. Parts name

No. Parts name

1 Compressor 15 Accumulator

2 Discharge temperature switch 16 Heat exchanger cooling electric control box

3 High pressure switch T3 Heat exchanger temperature sensor

4 High pressure sensor T4 Outdoor ambient temperature sensor

5 Oil separator T6A Plate heat exchanger inlet temperature sensor

6 Four-way valve T6B Plate heat exchanger outlet temperature sensor

7 Heat exchanger T7C1 Compressor A discharge temperature sensor

8 Electronic expansion valve (EXV) T7C2 Compressor B discharge temperature sensor

9 Low pressure switch SV4 Oil return valve

10 Fan motor SV5 Fast defrosting (in heating) and unloading (in cooling) valve

11 Fan SV6 Refrigerant bypass EXV valve

12 Stop valve (liquid side) SV7 Refrigerant bypass indoor units valve

13 Stop valve (gas side) SV8A Compressor A vapor injection valve


2

1 15 129

3

45

6

1110

7

14

8 8

8

13

EXVA EXVB

EXVC

ES

CT3

T4

T7C1

T7C

2

T6B

T6A

SV8A SV

4

SV7

SV5

SV6

16

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18/20/22HP


Legend

No. Parts name

No. Parts name












12 Stop valve (liquid side) SV8A Compressor A vapor injection valve

13 Stop valve (gas side) SV8B Compressor B vapor injection valve

14 Plate heat exchanger SV9 Compressor B pressure balance valve

7

1 1 15 129

34 5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6B

T6

A

SV8A

SV8B

SV9

SV4

SV5

SV6

2

16

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24/26/28HP


Legend

No. Parts name

No. Parts name















7

11 15 15 129

34 5

6

1110

1110

14

8

8

8 SV6

13

EXVBEXVA

EXVC

ES C T3

T4

T6B

T6A

SV8

A

SV8

B

SV4

SV9

SV5

T7C1 T7C2

2 2

16

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30/32HP

Figure 2-2.5: 30/32HP piping diagram

Legend

No. Parts name

No. Parts name

1 Compressor 16 Heat exchanger cooling electric control box

2 Discharge temperature switch T3 Heat exchanger temperature sensor

3 High pressure switch T4 Outdoor ambient temperature sensor

4 High pressure sensor T6A Plate heat exchanger inlet temperature sensor

5 Oil separator T6B Plate heat exchanger outlet temperature sensor

6 Four-way valve T7C1 Compressor A discharge temperature sensor

7 Heat exchanger T7C2 Compressor B discharge temperature sensor

8 Electronic expansion valve (EXV) SV4 Oil return valve

9 Low pressure switch SV5 Fast defrosting (in heating) and unloading (in cooling) valve

10 Fan motor SV6 Refrigerant bypass EXV valve

11 Fan SV7 Refrigerant bypass indoor units valve




15 Accumulator

7

11 1515 129

34 5

6

1110

1110

14

8 8

8

13

EXVBEXVA

EXVC

ES

C

SV6

T3

T4

T6B

T6A

SV5

SV9

SV7

SV4

SV8

A

SV8B

T7C1 T7C2

2 2

16

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Key components:

1. Oil separator:

Separates oil from gas refrigerant pumped out of the compressor and quickly returns it to the compressor. Separation

efficiency is up to 99%.

2. Accumulator:

Stores liquid refrigerant and oil to protect compressor from liquid hammering.

3. Electronic expansion valve (EXV):

Controls refrigerant flow and reduces refrigerant pressure.

4. Four-way valve:

Controls refrigerant flow direction. Closed in cooling mode and open in heating mode. When closed, the heat

exchanger functions as a condenser; when open, the heat exchanger functions as an evaporator.

5. Plate heat exchanger:

In cooling mode, it can improve super-cooling degree and the super-cooled refrigerant can achieve better heat

exchange in indoor side. In heating mode, the refrigerant comes from the plate heat exchanger going to the

compressor can enhance the refrigerant enthalpy and improve the heating capacity in low ambient temperature.

Refrigerant volume in plate heat exchanger is controlled according to temperature different between plate heat

exchanger inlet and outlet.

6. Solenoid valve SV4:

Returns oil to the compressor. Opens once the compressor has run for 200 seconds and closes 600 seconds later and

then opens for 3 minutes every 20 minutes.


Enables fast defrosting in heating mode and unloading in cooling mode. During defrosting operation, opens to

shorten the refrigerant flow cycle and quicken the defrosting process. In cooling mode, SV5 opens when outdoor

ambient temperature is above 40oC or compressor frequency is below 41Hz.


Allows refrigerant to bypass the expansion valves. Opens in cooling mode when discharge temperature exceeds the

limit. Closed in heating mode and standby.


Allows refrigerant to return directly to the compressor. Opens when indoor air temperature is close to the set

temperature to avoid frequent compressor on/off.

10. Solenoid valve SV8A / SV8B:

Allows refrigerant from plate heat exchanger inject directly to the compressor. SV8A opens when compressor A

startup and closes when compressor A stop. SV8B delays opening when compressor B startup and closes when

compressor B stop.


Balances compressor B pressure. Opens before compressor B startup and closed after compressor B running for 15

seconds. Opens after compressor B stops 10s and keep opening 60s.

12. High and low pressure switches:

Regulate system pressure. When system pressure rises above the upper limit or falls below the lower limit, the high or

low pressure switches turn off, stopping the compressor. After 10 minutes, the compressor restarts.

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3 Refrigerant Flow Diagrams

8/10/12HP

Cooling operation

Figure 2-3.1: 8/10/12HP refrigerant flow during cooling operation

Oil return operation in cooling mode

Figure 2-3.2: 8/10/12HP refrigerant flow during oil return operation in cooling mode

7

115

129

3

2

45

6

11

10

14

8

13

EXVA

EXVC

E SC

T3

T4

T6B

T7C1

T7

C2

T6

A

SV8A SV

4

SV5

SV6

Closed

FilterFilter

Closed

Unit onThermostat off

Unit onThermostat on


Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

FilterFilter

Normal control

FilterFilter

High temperature, high pressure gasHigh temperature, high pressure liquidMedium temperature, medium pressure gasLow temperature, low pressure

Fanon

Fanoff

Fanon

Fanon

7

115

129

3

2

45

6

11

10

14

8

13


EXVA

EXVC

E SC

T3

T4

T6B

T7C1

T7C

2

T6

A

SV8A SV

4

SV5

SV6

300 steps

FilterFilter

300 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

16

16

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Oil return operation in heating mode and defrosting operation

Figure 2-3.3: 8/10/12HP refrigerant flow during oil return operation in heating mode and during defrosting operation

Heating operation

Figure 2-3.4: 8/10/12HP refrigerant flow during heating operation

7

115

129

3

2

45

6

11

10

14

8

13


EXVA

EXVC

E SC

T3

T4

T6B

T7C1

T7C

2

T6

A

SV8A SV

4

SV5

SV6

480 steps

FilterFilter

480 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

480 steps

FilterFilter

480 steps

FilterFilter

Fanoff

Fanoff

Fanoff

Fanoff


7

115

129

3

2

45

6

11

10

14

8

13

EXVA

EXVC

E SC

T3

T4

T6B

T7C1

T7C

2

T6A

SV8A SV

4

SV5

SV6

Closed

Closed

FilterFilter




Unit off

Filter Ind

oo

r u

nit

op

era

tio

n

Filter

Normal control

Normal control

FilterFilter

FilterFilter

Fanon

Fanoff

Fanon

Fanon

16

16

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14/16HP

Cooling operation

Figure 2-3.5: 14/16 refrigerant flow during cooling operation


Figure 2-3.6: 14/16HP refrigerant flow during oil return operation in cooling mode

SV7

7

115

129

3

2

45

6

11

10

14

13

EXVC

E SC

T3

T4

T6B

T7C1

T7C

2

T6A

SV8

A SV4

SV5


EXVA EXVB8 8 SV

6Closed

FilterFilter

Closed




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

SV7

EXVA EXVB8 8 SV

67

115

129

3

2

45

6

11

10

14

13


EXVC

E SC

T3

T4

T6

B

T7C1

T7C

2

T6A

SV8A SV

4

SV5

300 steps

FilterFilter

300 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

16

16

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Figure 2-3.7: 14/16HP refrigerant flow during oil return operation in heating mode and during defrosting operation

Heating operation

Figure 2-3.8: 14/16HP refrigerant flow during heating operation

SV7

EXVA EXVB8 8 SV

67

115

129

3

2

45

6

11

10

14

13


EXVC

E SC

T3

T4

T6B

T7C1

T7C

2

T6A

SV8

A SV4

SV5

480 steps

FilterFilter

480 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

480 steps

FilterFilter

480 steps

FilterFilter

Fanoff

Fanoff

Fanoff

Fanoff

SV7

EXVA EXVB8 8 SV

6


7

115

129

3

2

45

6

11

10

14

13

EXVC

E SC

T3

T4

T6B

T7C1

T7C

2

T6A

SV8

A SV4

SV5

Closed

Closed

FilterFilter




Unit off

Filter Ind

oo

r u

nit

op

era

tio

n

Filter

Normal control

Normal control

FilterFilter

FilterFilter

Fanon

Fanoff

Fanon

Fanon

16

16

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18/20/22HP

Cooling operation

Figure 2-3.9: 18/20/22 refrigerant flow during cooling operation



7

1 1 15

16

129

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6

BT

6A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


Closed

FilterFilter

Closed




Unit off

Filter Ind

oo

r u

nit

op

era

tio

n

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

16

300 steps

FilterFilter

300 steps




Unit off

Filter Ind

oo

r u

nit

op

era

tio

n

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

7

1 1 1512

9

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6

BT

6A

SV8

A

SV8

B

SV9

SV4

SV5

SV6

2


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Heating operation


16

480 steps

FilterFilter

480 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

480 steps

FilterFilter

480 steps

FilterFilter

Fanoff

Fanoff

Fanoff

Fanoff

7

1 1 1512

9

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2T6

BT6

A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


Closed

Closed

FilterFilter




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

Normal control

FilterFilter

FilterFilter

Fanon

Fanoff

Fanon

Fanon

7

1 1 1512

9

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6B

T6A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


16

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24/26/28HP

Cooling operation

Figure 2-3.13: 24/26/28 refrigerant flow during cooling operation



16

15 15

7

1 112

9

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6B

T6A

SV8

A

SV8

B

SV9

SV4

SV5

SV6

2


Closed

FilterFilter

Closed




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

16

300 steps

FilterFilter

300 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

15 15

7

1 112

9

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6

BT

6A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


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Heating operation


16

480 steps

FilterFilter

480 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

480 steps

FilterFilter

480 steps

FilterFilter

Fanoff

Fanoff

Fanoff

Fanoff

15 15

7

1 112

9

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2T6

BT6

A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


Closed

Closed

FilterFilter




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

Normal control

FilterFilter

FilterFilter

Fanon

Fanoff

Fanon

Fanon

15 15

7

1 112

9

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6B

T6A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


16

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30/32HP

Cooling operation

Figure 2-3.17: 30/32 refrigerant flow during cooling operation


Figure 2-3.18: 30/32HP refrigerant flow during oil return operation in cooling mode

16

15 15

7

1 112

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6B

T6A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


Closed

FilterFilter

Closed




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

9

SV7

16

300 steps

FilterFilter

300 steps




Unit off

Filter Ind

oo

r u

nit

op

era

tio

n

Filter

Normal control

FilterFilter

Normal control

FilterFilter

Fanon

Fanoff

Fanon

Fanon

15 15

7

1 112

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6B

T6A

SV8

A

SV8

B

SV9

SV4

SV5

SV6

2


9

SV7

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Figure 2-3.19: 30/32HP refrigerant flow during oil return operation in heating mode and during defrosting operation

Heating operation

Figure 2-3.20: 30/32HP refrigerant flow during heating operation

16

480 steps

FilterFilter

480 steps




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

480 steps

FilterFilter

480 steps

FilterFilter

Fanoff

Fanoff

Fanoff

Fanoff

15 15

7

1 112

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2T6

BT6

A

SV8A

SV8B

SV9

SV4

SV5

SV6

2


9

SV7

Closed

Closed

FilterFilter




Unit off

Filter Ind

oo

r u

nit

op

erat

ion

Filter

Normal control

Normal control

FilterFilter

FilterFilter

Fanon

Fanoff

Fanon

Fanon

15 15

7

1 112

34

5

6

11 1110 10

14

88

8

13

EXVBEXVA

EXVC

E S CT3

T4

2

T7C1 T7C2

T6

BT

6A

SV8

A

SV8

B

SV9

SV4

SV5

SV6

2


9

SV7

16

V6 VRF 50Hz

32

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Part 3

Control

1 General Control Scheme Flowchart ...................................................... 34

2 Stop Operation .................................................................................... 35

3 Standby Control ................................................................................... 35

4 Startup Control .................................................................................... 36

5 Normal Operation Control ................................................................... 38

6 Protection Control ............................................................................... 43

7 Special Control ..................................................................................... 45

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1 General Control Scheme Flowchart

Sections 3-2 to 3-7 on the following pages detail when each of the controls in the flowchart below is activated.

Legend

Numbers in the top right-hand corners of boxes indicate the

relevant section of text on the following pages.

Conditions met

for oil return

Conditions met

for defrosting

Thermo on

Special control

Outdoor unit duty cycling

Oil return operation

Defrosting operation

7

Stop operation

Abnormal shutdown

System stops

A unit stops when the load demanded decreases

2

Standby control

Crankcase heater control

3

Startup control

Compressor startup delay control

Startup control for cooling operation

Startup control for heating operation

4

Thermo on

Normal operation control

Component control during normal operation

Compressor output control

Compressor step control

Operation priority and rotation of compressors

Electronic expansion valve control

Outdoor fan control

5

Protection control

High pressure protection control

Low pressure protection control

Discharge temperature protection control

Compressor and inverter module protection

control

Disable heating control

6

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2 Stop Operation

The stop operation occurs for one of the three following reasons:

1. Abnormal shutdown: in order to protect the compressors, if an abnormal state occurs the system makes a 'stop with

thermo off' operation and an error code is displayed on the outdoor unit digital displays.

2. The system stops when the set temperature has been reached.

3. A unit stops when the load demanded by the indoor units decreases and can be handled by fewer outdoor units.

When a unit stops because the load demanded by the indoor units has decreased and can be handled by fewer outdoor

units, the unit's four-way valve remains on until the load demanded by the indoor units increases and the unit is required

to operate. When the whole system stops, all the units' four-way valves turn off.

3 Standby Control

3.1 Crankcase Heater Control

The crankcase heater is used to prevent refrigerant from mixing with compressor oil when the compressors are stopped.

The crankcase heater is controlled according to outdoor ambient temperature and discharge temperature. When the

outdoor ambient temperature is above 40°C, the crankcase heater is off; when the outdoor ambient temperature is below

35°C, the crankcase heater is controlled according to discharge temperature. Refer to Figures 3-3.1 and 3-3.2.

Figure 3-3.1: Crankcase heater controlled according to outdoor ambient temperature

Figure 3-3.2: Crankcase heater controlled according to discharge temperature

Ambient temperature < 35 oC Ambient temperature > 40 oC

Crankcase heater off

Crankcase heater is controlled according to discharge temperature

Discharge temperature < 40 oC Discharge temperature > 50 oC

Crankcase heater off

Crankcase heater on

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4 Startup Control

4.1 Compressor Startup Delay Control

In initial startup control, compressor startup is delayed for 12 minutes in order to let the master unit search for the indoor

units’ addresses. In restart control (except in oil return operation and defrosting operation), compressor startup is delayed

such that a minimum of 7 minutes has elapsed since the compressor stopped, in order to prevent frequent compressor

on/off and to equalize the pressure within the refrigerant system.

4.2 Startup Control for Cooling Operation Table 3-4.1: Component control during startup in cooling mode

Component

Wiring

diagram

label

8-12HP 14-16HP 18-28HP 30-32HP Control functions and states

Inverter compressor A COMP(A) Controlled according to load requirement, operating

frequency increased by 1 step / sec Inverter compressor B COMP(B)

DC fan motor A FANA Fan speed1 controlled according to discharge

pressure (Pc):

At initial speed for 90 seconds.

Subsequently, Pc checked every 10 seconds:

Pc ≥ 2.7MPa => 1 step increase.

Pc ≤ 2.1MPa => 1 step decrease.

DC fan motor B FANB

Electronic expansion valve

A EXVA

Position (steps) from 0 (fully closed) to 480 (fully

open), controlled according to discharge temperature Electronic expansion valve

B EXVB


C EXVC


open), controlled according to temperature different

between plate heat exchanger inlet and outlet

Four-way valve ST1 Off

Solenoid valve (oil

balance) SV4 Closed for 200 secs, open for 600 secs, then closed

Solenoid valve (fast

defrosting (in heating) and

unloading (in cooling))

SV5 Open for 4 mins, then closed

Solenoid valve (EXV

bypass) SV6

Open for 10 mins, then controlled according to

pressure

Solenoid valve (indoor

units bypass) SV7

Controlled according to load requirement

Solenoid valve (inverter

compressor A vapor

injection)

SV8A Controlled according to inverter compressor A


compressor B vapor

injection)

SV8B Controlled according to inverter compressor B


compressor B pressure

balance)

SV9 Open before compressor B startup

Notes:

1. Refer to Table 3-5.3 in Part 3, 5.6 “Outdoor Fan Control” for more information on fan speed steps.

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4.3 Startup Control for Heating Operation Table 3-4.2: Component control during startup in heating mode

Component

Wiring

diagram

label


Inverter compressor A COMP(A) Controlled according to load requirement,

operating frequency increased by 1 step / sec Inverter compressor B COMP(B)

DC fan motor A FANA Open once the four-way valve has opened,

controlled according to outdoor ambient

temperature and load requirement DC fan motor B FANB


A EXVA Position (steps) from 0 (fully closed) to 480 (fully

open), controlled according to discharge superheat Electronic expansion valve B EXVB

Electronic expansion valve C EXVC


open), controlled according to temperature

different between plate heat exchanger inlet and

outlet

Four-way valve ST1 On

Solenoid valve (oil balance) SV4 Closed for 200 secs, open for 600 secs, then closed




SV5 Open for 4 mins, then closed

Solenoid valve (EXV bypass) SV6 Off

Solenoid valve (indoor units

bypass) SV7



compressor A vapor

injection)

SV8A Controlled according to inverter compressor A


compressor B vapor

injection)

SV8B Controlled according to inverter compressor B



balance)

SV9 Open before compressor B startup

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5 Normal Operation Control

5.1 Component Control during Normal Operation Table 3-5.1: Component control during normal cooling operation

Component

Wiring

diagram

label


Inverter compressor A COMP(A)

Controlled according to load requirement Inverter compressor B COMP(B)

DC fan motor A FANA Controlled according to discharge pressure

DC fan motor B FANB


A EXVA


open), controlled according to discharge

temperature Electronic expansion valve

B EXVB


C EXVC




outlet


Solenoid valve (oil balance) SV4 Open regularly




SV5

Controlled according to ambient temperature,

discharge pressure, discharge temperature,

compressor running frequency and discharge

superheat

Solenoid valve (EXV

bypass) SV6

Controlled according to discharge pressure and

discharge temperature


units bypass) SV7



compressor A vapor

injection)

SV8A

Controlled according to inverter compressor A

on/off


compressor B vapor

injection)

SV8B

Controlled according to inverter compressor B

on/off



balance)

SV9

Open before compressor B startup and close after

compressor B running for 15 seconds. Open after

compressor B stop 10 seconds and keep open 60

seconds.

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Table 3-5.2: Component control during heating operation

Component

Wiring

diagram

label



Controlled according to load requirement Inverter compressor B COMP(B)

DC fan motor A FANA Controlled according to outdoor ambient

temperature, outdoor heat exchanger pipe

temperature, discharge pressure and load

requirement

DC fan motor B FANB


A EXVA


open), controlled according to discharge superheat Electronic expansion valve

B EXVB


C EXVC




outlet


Solenoid valve (oil balance) SV4 Open regularly




SV5

Controlled according to ambient temperature,

discharge pressure, discharge temperature,

compressor running frequency and discharge

superheat

Solenoid valve (EXV

bypass) SV6 Off


units bypass) SV7



compressor A vapor

injection)

SV8A

Controlled according to inverter compressor A

on/off


compressor B vapor

injection)

SV8B

Controlled according to inverter compressor B

on/off



balance)

SV9

Open before compressor B startup and close after

compressor B running for 15 seconds. Open after

compressor B stop 10 seconds and keep open 60

seconds.

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5.2 Compressor Output Control

The compressor rotation speed is controlled according to the load requirement. Before compressor startup, the outdoor

units first estimate the indoor unit load requirement according to the nominal capacity of indoor units currently running,

and then correct for ambient temperature. The compressors then start up according to the corrected load requirement.

During operation the compressors are controlled according to the nominal capacity of indoor units currently running and

the indoor unit heat exchanger temperatures. If the actual load requirement can be provided by one unit alone, then only

one unit starts up. If the actual load requirement requires all outdoor unit modules to operate, the weighted average

actual load requirement is sent to each module and each module operates according to this distributed load

requirement.

5.3 Compressor Step Control

The running speed of the compressors in rotations per second (rps) is one third of the frequency (in Hz) of the electrical

input to the compressor motors. The compressor speed can be altered in increments of 1 rps.

5.4 Operating Priority and Rotation of Compressors

Figures 3-5.1 to 3-5.4 show the compressor operating priority and rotation in systems with one, two, three and four

outdoor units. In units with two compressors, inverter compressor A (BP1) operates in priority to inverter compressor B

(BP2). In multi-unit systems, units operate in rotation. In Figures 3-5.2 to 3-5.4 the master unit and slave units 1, 2 and 3

are shown from left to right in that order, and the circled numbers (①, ②, ③, ④) indicate the rotation sequence.

Figure 3-5.1: Compressor priority and rotation – one outdoor unit

Figure 3-5.2: Compressor priority and rotation – two outdoor units

BP

No. 1

BP1

No. 1 No. 2

BP2

BP BP

No. 1 No. 2

No. 2 No. 1

BP1

No. 1 No. 2 No. 3

No. 2 No. 3 No. 1

BP2 BP BP

1

BP1

No. 1 No. 2 No. 3 No. 4

BP2

No. 3 No. 4 No. 1 No. 2

BP2

①

②

①

②

①

②

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Figure 3-5.3: Compressor priority and rotation – three outdoor units

5.5 Electronic Expansion Valve Control

EXVA and EXVB control

The positions of electronic expansion valves EXVA and EXVB are controlled in steps from 0 (fully closed) to 480 (fully

open).

In cooling mode:

When all outdoor units are in standby:

All EXVAs and EXVBs are at position 352 (steps).

When some outdoor units are running and some outdoor units are in standby:

EXVAs and EXVBs on running outdoor units are controlled according to discharge temperature. EXVAs and EXVBs

of units in standby are fully closed.

When all outdoor units are running:

All EXVAs and EXVBs are controlled according to discharge temperature.

In heating mode:


All EXVAs and EXVBs are at position 352 (steps).


EXVAs and EXVBs on running outdoor units are controlled according to discharge superheat. EXVAs and EXVBs of

units in standby are fully closed.


All EXVAs and EXVBs are controlled according to discharge superheat.

EXVC control

The positions of electronic expansion valves EXVC are controlled in steps from 0 (fully closed) to 480 (fully open).

In cooling / heating mode:


BP BP

No. 1 No. 2 No. 3

No. 3 No. 1 No. 2

BP

No. 2 No. 3 No. 1

BP

No. 1 No. 2 No. 3 No. 4

No. 3 No. 4 No. 1 No. 2

BP

No. 2 No. 3 No. 4 No. 1

BP1 BP2

BP1 BP2

No. 1 No. 2 No. 3 No. 4 No. 5

BP

No. 4 No. 5 No. 1 No. 2 No. 3

No. 2 No. 3 No. 4 No. 5 No. 1

BP1 BP2 BP1 BP2 BP1 BP2

No. 3 No. 4 No. 5 No. 6 No. 1 No. 2

No. 1 No. 2 No. 3 No. 4 No. 5 No. 6

No. 5 No. 6 No. 1 No. 2 No. 3 No. 4

BP1 BP2

①

②

③

①

②

③

①

②

③

①

②

③

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All EXVCs are fully closed.


EXVCs on running outdoor units are controlled according to temperature different between plate heat exchanger

inlet and outlet. EXVCs of units in standby are fully closed.


All EXVCs are controlled according to temperature different between plate heat exchanger inlet and outlet.

5.6 Outdoor Fan Control

The speed of the outdoor unit fans is adjusted in steps, as shown in Table 3-5.3.

Table 3-5.3: Outdoor fan speed steps

Fan speed index

Fan speed (rpm)

8-16HP 18-22HP 24-32HP

FANA / FANB FANA / FANB

0 0 0 / 0 0 / 0

1 120 150 / 0 120 / 0

2 150 190 / 0 150 / 0

3 170 230 / 0 170 / 0

4 190 270 / 0 190 / 0

5 210 310 / 0 (150 / 150) 210 / 0

6 230 350 / 0 (180 / 180) 230 / 0

7 250 380 / 0 (210 / 210) 250 / 0 (120 / 120)

8 270 410 / 0 (240 / 240) 270 / 0 ( 150 / 150)

9 290 280 / 280 330 / 0 (170 / 170)

10 310 320 / 320 370 / 0 (190 / 190)

11 330 360 / 360 210 / 210

12 350 400 / 400 230 / 230

13 370 440 / 440 250 / 250

14 390 480 / 480 270 / 270

15 410 520 / 520 290 / 290

16 430 560 / 560 310 / 310

17 450 600 / 600 330 / 330

18 470 640 / 640 350 / 350

19 490 680 / 680 370 / 370

20 510 720 / 720 400 / 400

21 530 760 / 760 430 / 430

22 560 800 / 800 470 / 470

23 580 840 / 840 510 / 510

24 600 880 / 880 550 / 550

25 630 910 / 910 600 / 600

26 650 940 / 940 650 / 650

27 700 980 / 980 700 / 700

28 750 1010 / 1010 750 / 750

29 800 1020 / 1020 800 / 800

30 850 1050 / 1050 830 / 830

31 880 1080 / 1080 850 / 850

32 920 1120 / 1120 870 / 870

33 920 1140 / 1140 890 / 890

34 920 1140 / 1140 920 / 920

35 920 1140 / 1140 920 / 920

36 (ESP 40Pa mode) 950 1200 / 1200 950 / 950

37 (ESP 60Pa mode) 980 1200 / 1200 980 / 980

Note:

1. For 18-22HP unit fan speed 5 to 8 and 24-32HP unit fan speed 7 to 10, when fan speed decreases, the fan speed is shown in the bracket; when fan speed

increases, the fan speed is shown without bracket.

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6 Protection Control

6.1 High Pressure Protection Control

This control protects the system from abnormally high pressure and protects the compressors from transient spikes in

pressure.

Figure 3-6.1: High pressure protection control

Notes:

1. Pc: Discharge pressure

6.2 Low Pressure Protection Control

This control protects the system from abnormally low pressure and protects the compressors from transient drops in

pressure.

Figure 3-6.2: Low pressure protection control

Notes: 1. Pe: Suction pressure

6.3 Discharge Temperature Protection Control

This control protects the compressors from abnormally high temperatures and transient spikes in temperature. It is

performed for each compressor.

Figure 3-6.3: Discharge temperature protection control

When the discharge temperature rises above 120°C the system displays P4 protection and all units stop running. When P4

protection occurs 3 times in 100 minutes, the H6 error is displayed. When an H6 error occurs, a manual system restart is

required before the system can resume operation.

6.4 Compressor and Inverter Module Protection Control

This control protects the compressors from abnormally high currents and protects the inverter modules from abnormally

Pc > 4.4MPa Pc < 3.2MPa

Normal operation

High pressure protection, error code P1 is displayed

Pe < 0.05MPa Pe > 0.15MPa

Normal operation

Low pressure protection, error code P2 is displayed

When P2 protection occurs 3 times

in 60 minutes, the H5 error is

displayed. When an H5 error occurs,

a manual system restart is required

before the system can resume

operation.

120oC

100oC

90oC

Discharge temperature

Compressor off

90oC

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high temperatures. It is performed for each compressor and inverter module.

Figure 3-6.4: Compressor current protection control

Compressor model AA55PHDG –D1YG DC80PHDG –D1YG

Currentmax 24.6 33

Figure 3-6.5: Inverter module temperature protection control

Notes:

1. Tf: Heat sink temperature

6.5 Disable Heating Control

When the outdoor ambient temperature rises above 25°C heating mode is disabled to prevent the mechanical load on

compressors becoming too high and to prevent low compression ratios which can result in insufficient compressor internal

oil lubrication.

Figure 3-6.6: Disable heating control

Current ≥ Currentmax Current < Currentmax

Normal operation

Compressor current protection, error code xP3 is displayed

Tf > 75oC Tf < 73oC

Normal operation

Compressor output reduced

Tf > 80oC

Tf < 65oC

Inverter module temperature protection,

error code PL is displayed

When PL protection occurs 3 times

in 100 minutes, the C7 error is

displayed. When a C7 error occurs, a

manual system restart is required

before the system can resume

operation.

Outdoor ambient temperature > 25oC Outdoor ambient temperature < 23oC

Heating operation

Units stop

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7 Special Control

7.1 Outdoor Unit Duty Cycling

In systems with multiple outdoor units, outdoor unit duty cycling is used to prevent compressor burn out due to

unbalanced oil levels between outdoor units.

Timing of outdoor unit duty cycling:

After oil return operation.

After defrosting operation.

On restart following compressor stop after set temperatures achieved.

Figure 3-7.1 shows an example of duty cycling in a system with 3 outdoor units.

Figure 3-7.1: Duty cycling in a system with 3 outdoor units1

Notes:

1. The address settings on the outdoor unit main PCBs for “master unit”, “slave unit 1”, and “slave unit 2” do not change.

7.2 Oil Return Operation

In order to prevent compressors from running out of oil, the oil return operation is conducted to recover oil that has

flowed out of the compressor(s) and into the piping system. This operation is performed for all units including units that

are in standby. When the outdoor unit is running in oil return, the digital display on outdoor main PCB will display “d0”.

Timing of oil return operation:

When the initial cumulative operating time reaches 140 minutes and then every 8 hours.

Startup control

Normal operation

After oil return operation or

after defrosting operation or

on restart following compressor

stop after set temperatures

achieved Normal operation

Outdoor unit

duty cycling

Priority

1

Priority

2

Priority

3

Master Slave 1 Slave 2

Outdoor unit

duty cycling

Priority

3

Priority

1

Priority

2

Master Slave 1 Slave 2

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Tables 3-7.1 and 3-7.2 show component control during oil return operation in cooling mode.

Table 3-7.1: Outdoor unit component control during oil return operation in cooling mode

Component Wiring diagram

label 8-12HP 14-16HP 18-28HP 30-32HP Control functions and states


Fixed frequency Inverter compressor B COMP(B)

DC fan motor A FANA Fan speed controlled according to

discharge pressure DC fan motor B FANB

Electronic expansion valve A EXVA

Position 480 (steps) Electronic expansion valve B EXVB

Electronic expansion valve C EXVC Position 96 (steps)


Solenoid valve (oil balance) SV4 Normal control

Solenoid valve (fast defrosting (in

heating) and unloading (in cooling)) SV5 On

Solenoid valve (EXV bypass) SV6 On

Solenoid valve (indoor units bypass) SV7 Normal control

Solenoid valve (inverter compressor

A vapor injection) SV8A

Controlled according to inverter

compressor A


B vapor injection) SV8B

Controlled according to inverter

compressor B


B pressure balance) SV9 Open before compressor B startup

Table 3-7.2: Indoor unit component control during oil return operation in cooling mode

Component Unit state Control functions and states

Fan

Thermo on Remote controller setting

Standby Off

Thermo off Off


Thermo on Normal control

Standby 300 (steps)

Thermo off 300 (steps)

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Tables 3-7.3 and 3-7.4 show component control during oil return operation in heating mode.

Table 3-7.3: Outdoor unit component control during oil return operation in heating mode





DC fan motor A FANA Fan speed controlled according to

discharge pressure DC fan motor B FANB











A vapor injection) SV8A Off


B vapor injection) SV8B Off



Table 3-7.4: Indoor unit component control during oil return operation in heating mode


Fan

Thermo on Off

Standby Off

Thermo off Off


Thermo on 480 (steps)

Standby 480 (steps)


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7.3 Defrosting Operation

In order to recover heating capacity, the defrosting operation is conducted when the outdoor unit heat exchanger is

performing as an evaporator. The defrosting operation is controlled according to outdoor ambient temperature, outdoor

heat exchanger temperature, indoor heat exchanger temperature and outdoor units running time. When the outdoor unit

is running in defrosting, the digital display on outdoor main PCB will display “df”.

Table 3-7.5: Outdoor unit component control during defrosting operation





DC fan motor A FANA

Off DC fan motor B FANB











A vapor injection) SV8A Off


B vapor injection) SV8B Off



Table 3-7.6: Indoor unit component control during defrosting operation


Fan

Thermo on Off

Standby Off

Thermo off Off


Thermo on 480 (steps)

Standby 480 (steps)


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Settings

Part 4

Field Settings

1 Outdoor Unit Field Settings ................................................................. 50

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1 Outdoor Unit Field Settings

1.1 PCB Switches and Switch Settings Figure 4-1.1: Outdoor unit main PCB switches

Table 4-1.1: Outdoor unit main PCB switch settings

Switch Setting Switch positions1 Description

S4 Static pressure

Standard static pressure (default)

Low static pressure mode (reserved)

Medium static pressure mode (reserved)

High static pressure mode (reserved)

Super high static pressure mode (reserved)

S5 Priority mode

2

Auto priority (default)

Cooling priority

VIP priority or voting priority

Heating only

Cooling only

Set priority mode via centralized controller (reserved)

S6-1 Reserved

Reserved

S6-2

Clear indoor unit addresses

No action (default)

Clear indoor unit addresses

Table continued on next page …

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Table 4-1.1: Outdoor unit main PCB switch settings (continued)

Switch Setting Switch positions1 Description

S6-3

Addressing

mode

Auto addressing (default)

Manual addressing

S8-1 Reserved

Reserved

S8-2 Start-up time

Start-up time is 12 minutes (default)

Start-up time is 7 minutes

S8-3 Reserved

Reserved

S7 Reserved

Reserved

S9 Reserved

Reserved

S13 Controller type

Use the new centralized controller (CCM-180A/WS & CCM-270A/WS) (default)

Use the old centralized controller

ENC1

Outdoor unit address

Only 0, 1, 2 should be selected (default is 0) 0 is for master unit; 1 and 2 are for slave units

ENC2

Outdoor unit capacity3

Only 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C should be selected 0: 8HP; 1: 10HP; 2: 12HP; 3: 14HP; 4: 16HP; 5: 18HP; 6: 20HP; 7: 22HP; 8: 24HP; 9: 26HP; A: 28HP; B:30HP; C:32HP

ENC4

Network address

Only 0, 1, 2, 3, 4, 5, 6, 7 should be selected (default is 0)

ENC3 S12

Number of indoor units

The number of indoor units is in the range 0-15 0-9 on ENC3 indicate 0-9 indoor units; A-F on ENC3 indicate 10-15 indoor units




ENC4 Silent mode4

0 Night silent time is 6h/10h (default)

1 Night silent time is 6h/12h



4 No silent mode

5 Silent mode 1 (only limit max. fan speed)



8 Super silent mode 1 (limit max. fan speed and compressor frequency)


A Super silent mode 3 (limit max. fan speed and compressor frequency)

B Super silent mode 4 (limit max. fan speed and compressor frequency)

F Set silent mode via centralized controller (reserved) Notes:

1. Black denotes the switch position.

2. Refer to Part 4, 1.2.1 “Priority mode setting”.

3. Switch ENC2 is factory-set and its setting should not be changed.

4. Refer to Part 4, 1.2.2 “Silent mode setting”.

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1.2 Modes Set on Main PCB

1.2.1 Priority mode setting

Priority mode can only be set on the master unit. When an indoor unit is in mode conflict with the outdoor units the unit

displays the mode conflict error. If the indoor unit has a digital display, it will display error code E0; if the indoor unit

display board has LED indicators, the “DEF./FAN” LED will flash rapidly.

Figure 4-1.2: Indoor unit digital displays and LED indicators

There are five priority mode options:

1. Auto priority mode (default): In auto priority mode, the outdoor unit will operate in heating priority mode or cooling

priority mode according to the outdoor ambient temperature.

a) When the outdoor ambient temperature is below 13oC, the outdoor units run in heating priority mode. The

heating priority mode does not change until the outdoor ambient temperature is above 18oC.

b) When the outdoor ambient temperature is above 18oC, the outdoor units run in cooling priority mode. The

cooling priority mode does not change until the outdoor ambient temperature is below 13oC.

c) When the outdoor units restart under the outdoor ambient between 13oC and 18oC, the outdoor units run the

same priority as before the last stop.

d) When the outdoor unit is initial startup under outdoor ambient temperature between 13oC and 18oC, the

outdoor units run in heating priority mode.

Figure 4-1.3: Auto priority mode control

1.1. Heating priority mode:

a) During cooling operation: If an indoor unit requests heating, the outdoor units stop and then restart in heating

mode after 5 minutes. Indoor units requesting heating then start in heating mode and indoor units requesting

cooling display the mode conflict error.

b) During heating operation: If an indoor unit requests cooling, the outdoor units ignore the request and continue

to run in heating mode. The indoor unit requesting cooling displays the mode conflict error. If all the indoor units

requesting heating are later turned off and one or more indoor units are still requesting cooling, the outdoor

units restart in cooling mode after 5 minutes and any indoor units requesting cooling then start in cooling mode.

1.2. Cooling priority mode:

a) During heating operation: If an indoor unit requests cooling, the outdoor units stop and then restart in cooling

mode after 5 minutes. Indoor units requesting cooling then start in cooling mode and indoor units requesting

heating display the mode conflict error.

b) During cooling operation: If an indoor unit requests heating, the outdoor units ignore the request and continue

to run in cooling mode. The indoor unit requesting heating displays the mode conflict error. If all the indoor units

requesting cooling are later turned off and one or more indoor units are still requesting heating, the outdoor

units restart in heating mode after 5 minutes and any indoor units requesting heating then start in heating

DEF./FAN LED Digital display

18oC

13oC

Outdoor ambient temperature

Cooling priority

Heating priority

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mode.

2. Cooling priority mode: refer to above “1.2. Cooling priority mode” descriptions.

3. VIP priority mode or voting priority mode: The default VIP address is 63, the VIP address also can be changed

through menu mode, refer to Part 5, 1.2.3 “Menu mode” Table 5-1.3 “nb8”. If the VIP indoor unit is operating, the

outdoor units operate in the mode of the VIP indoor unit. Indoor units that are in a mode different to that of the VIP

unit display the mode conflict error. If there is no unit with VIP address or the VIP unit is in standby, the outdoor units

operate in voting priority mode. In voting priority mode, the outdoor units operate in whichever of heating and

cooling modes is being requested by the larger number of indoor units.

4. Heating only mode: The outdoor units only operate in heating mode. Indoor units requesting heating operate in

heating mode. Indoor units requesting cooling or in fan only mode display the mode conflict error.

5. Cooling only mode: The outdoor units only operate in cooling mode. Indoor units requesting cooling operate in

cooling mode; indoor units in fan only mode operate in fan only mode. Indoor units requesting heating display the

mode conflict error.

1.2.2 Silent time setting

1.2.2.1 Night silent time setting

Night silent mode is activated X hours after the peak daytime temperature, and is deactivated after Y hours, where X and Y

are as specified in Table 4-1.2. Table 4-1.2: Night silent time setting

Switch Switch positions Description X Y

ENC4

0 Night silent time is 6h/10h (default) 6 10

1 Night silent time is 6h/12h 6 12



Figure 4-1.2: Night silent mode example (default setting, 6h/10h)

Operation sound dB

Load

Maximum output

8:00 14:00 20:00 6:00

Night silent mode activated

The outdoor unit senses the peak daytime outdoor ambient temperature

6 10

Night silent mode deactivated

Max. 15dB reduction

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1.2.2.2 Silent mode setting

In silent mode 1 / 2 / 3, the outdoor fan speed decreases gradually. In super silent mode 1 / 2 / 3 / 4 and night silent mode,

not only the fan speed decreases gradually, but also the compressor frequency decreases gradually.

Table 4-1.3: Silent mode setting

Switch Switch positions Description

ENC4






A Super silent mode 3 (limit max. fan speed and compressor frequency)

B Super silent mode 4 (limit max. fan speed and compressor frequency)

1.2.2.3 Maximum fan speed and capacity output control in different silent mode

Table 4-1.4: Maximum fan speed and capacity output control in different silent mode

ENC4

Switch positions Description

Max. fan speed index1

Max.

capacity

output

8-10HP 12HP 14-16HP 18-22HP 24-26HP 28-32HP 8-32HP

0 Night silent time is 6h/10h (default)

28 28 28 22 28 28

100%




4 No silent mode 30 31 30 30 30 31

5 Silent mode 1 28 28 28 27 28 28

6 Silent mode 2 26 26 26 25 26 26

7 Silent mode 3 24 24 24 23 24 24

8 Super silent mode 1 28 28 28 22 28 28 80%

9 Super silent mode 2 27 27 27 21 27 27 70%

A Super silent mode 3 26 26 26 20 26 26 60%

B Super silent mode 4 25 25 25 19 25 25 50%

Notes: 1. Fan speed (rpm) for different fan speed index refers to Table 3-5.3 in Part 3, 5.6 “Outdoor Fan Control”.

2. If the system pressure is over 3.5MPa, the system exits silent mode automatically.

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Part 5

Electrical Components and

Wiring Diagrams

1 Outdoor Unit Electric Control Box Layout .............................................. 56

2 Outdoor Unit Main PCB ......................................................................... 58

3 Wiring Diagrams .................................................................................... 66

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1 Outdoor Unit Electric Control Box Layout

8-16HP

Figure 5-1.1: 8-16HP top layer of electric control box

Figure 5-1.2: 8-16HP bottom layer of electric control box

Power supplyterminals

Communicationterminals block

Inductor

Filter boardMain PCB

Invertermodule Reactor

Pipe temp. sensorCompressor connection wire

Fan module

Bridge rectifier

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18-32HP

Figure 5-1.3: 18-32HP top layer of electric control box

Figure 5-1.4: 18-32HP bottom layer of electric control box

Power supplyterminals

Communicationterminals block

Inductor

Inductor

Filter boardMain PCB

Invertermodule

Invertermodule Reactor Reactor

Fan module

Fan module

Pip

ete

mp

. sen

sor

Co

mp

ress

or

con

nec

tio

n w

irin

g

Co

mp

ress

or

con

nec

tio

n w

irin

g

Pip

ete

mp

. sen

sor

Bridge rectifier

Bridge rectifier

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2 Outdoor Unit Main PCB

2.1 Ports Figure 5-2.1: Outdoor unit main PCB ports

1

Notes: 1. Label descriptions are given in Table 5-2.1.

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Table 5-2.1: Main PCB ports

Label in

Figure 5-2.1 Port code Content Port voltage

1 CN18 Low pressure switch connection 0V or 5V DC

2 CN19 High pressure switch and discharge temperature switch(es)

connections 0V or 5V DC

3 CN4

Compressor top temperature sensor (single compressor

units) or compressor A compressor top temperature sensor

(dual compressor units) connection

0-5V DC (varying)

4 CN5

Discharge pipe temperature sensor (single compressor units)

or compressor B compressor top temperature sensor (dual

compressor units) connection

0-5V DC (varying)

5 CN3 Inverter module temperature sensor A connection 0-5V DC (varying)

6 CN3_1 Inverter module temperature sensor B connection 0-5V DC (varying)

7 CN17 High pressure sensor connection 0-5V DC (varying)

8 CN15 Inverter compressor A and B current sensor connections 0-7.8V AC (varying)

9 CN16 Reserved /

10 CN8 Plate heat exchanger inlet temperature sensor connection 0-5V DC (varying)

11 CN1 Outdoor ambient temperature sensor and outdoor heat

exchanger temperature sensor connections 0-5V DC (varying)

12 CN8_1 Plate heat exchanger outlet temperature sensor connection 0-5V DC (varying)

13 CN20 Communication port to outdoor units 2.5-2.7V DC

14 CN26 Communication port to compressor drive board 2.5-2.7V DC

15 CN27 Communication port to fan drive board 2.5-2.7V DC

16 CN25 Communication port 2.5-2.7V DC

17 CN28 Reserved /

18 CN71 EEVB drive port 0V or 12V DC

19 CN70 EEVA drive port 0V or 12V DC

20 CN72 EEVC drive port 0V or 12V DC

21 CN82 Control port of relay for AC filter board 0V or 12V DC

22 CN66-CN67 Power supply to compressor crankcase heater 220V AC

23 CN47 Four-way valve drive ports 220V AC

24 CN41-CN46;

CN83-CN85 Solenoid valve drive ports 220V AC

25 CN30 Power input of main board 220V AC between A/B/C and N;

380V AC between A,B and C

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2.2 Components

Layout 2.2.1

Figure 5-2.2: Outdoor unit main PCB components

Function of buttons SW3 to SW6 2.2.2

Table 5-2.2: Function of buttons SW3 to SW6

Button Function

SW3 (UP) In menu mode: previous and next buttons for menu

modes.

Not in menu mode: previous and next buttons for

system check information.

SW4 (DOWN)

SW5 (MENU) Enter / exit menu mode.

SW6 (OK) Confirm to enter specified menu mode.

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Menu mode 2.2.3

Only master unit has the full menu functions, slaves units only have error codes check and cleaning functions.

1. Long press SW5 “MENU” button for 5 seconds to enter menu mode, and the digital display displays “n1”;

2. Press SW3 / SW4 “UP / DOWN” button to select the first level menu “n1”, “n2”, “n3”, “n4”or “nb”;

3. Press SW6 “OK” button to enter specified first level menu, for example, enter “n4” mode;

4. Press SW3 / SW4 “UP / DOWN” button to select the second level menu from “n41” to “n47”;

5. Press SW6 “OK” button to enter specified second level menu, for example, enter “n43” mode;

Menu mode selection flowchart:

Start

Long press SW5 “MENU”

button for 5 seconds

Digital display displays “-n1”

Press SW3 / SW4 “UP /

DOWN” button to select

the first level menu “nX”

Digital display displays “-nX”

Press SW6 “OK” button

to enter specified first

level menu “-nX”

Digital display displays “-nX1”

Press SW3 / SW4 “UP /

DOWN” button to select the

second level menu “nXY”

Digital display displays “-nXY”

Press SW6 “OK” button to

enter specified second level

menu “-nXY”

Confirm “-nXY”

Sho

rt p

ress

SW

5

“MEN

U”

bu

tto

n

Sho

rt p

ress

SW

5

“MEN

U”

bu

tto

n

Sho

rt p

ress

SW

5

“MEN

U”

bu

tto

n

Sho

rt p

ress

SW

5

“MEN

U”

bu

tto

n

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Menu mode function:

Table 5-2.3: Menu mode function

Digital display

content Menu mode Remarks

n14 Debug mode 1 Only available for the master unit (all indoor units running in cooling mode)

n15 Debug mode 2

Only available for the master unit (if all the indoor unit in the system are the 2nd

generation indoor units, all the indoor units will run in heating mode. Once there is one or

more old indoor unit in the system, all the indoor units will run in force cooling mode)

n16 Maintenance mode Only available for the master unit, the system does not check the indoor units’ number.

n24 Reserved

n25 Reserved

n26 Backup run Only available for outdoor unit with two compressors. If one of the two compressors is

fail, the other compressor will keep running for up to 4 days and then stop automatically.

n27 Vacuum mode It is only used in maintenance process. The digital display displays “R006”, all solenoid

valves are open and EXVs are open to the maximum steps.

n31 History error codes Display recent ten history error codes

n32 Cleaning history error codes

n33 Reserved

n34 Factory reset Only available for the master unit

n41 Power limitation mode 1 Only available for the master unit, 100% capacity output







nb1 Fahrenheit degree setting (oF) Only available for the master unit

nb2 Celsius degree setting (oC) Only available for the master unit

nb3 Exit auto power save mode1 Only available for the master unit

nb4 Enter auto power save mode1 Only available for the master unit

nb5 Auto snow-blowing mode 1 (customized) According to outdoor ambient temperature (T4), the outdoor fan(s) periodically stop for

15 minutes and run for 2 minute

nb6 Auto snow-blowing mode 2 (customized) According to outdoor ambient temperature (T4), the outdoor fan(s) periodically stop for

30 minutes and run for 2 minute

nb7 Exit auto snow-blowing mode

nb8 VIP address setting The digital display will display “IdXX”, “XX” stands for VIP address, use UP / DOWN button

to change the VIP address and press OK button to confirm the specified VIP address.

nF1 Reserved

nF2 Reserved

Notes:

1. Auto power save mode means EMS mode, the evaporating temperature (in cooling) and condensing temperature (in heating) are automatically adjusted

according to both indoor and outdoor temperature to maximize the comfort and energy efficiency. Exit auto power save mode, the evaporating temperature

(in cooling) and condensing temperature (in heating) are fixed.

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How to exit specified menu mode:

Table 5-2.4: Exit specified menu mode method:

Menu mode Manual exit method Automatic exit method System restart

Debug mode 1 (2) Long press SW6 “OK” button when the digital

display is not in menu selection state After running 120 minutes Invalid

Maintenance mode / After running 60 minutes Invalid

Backup run / After running 4 days or both

two compressors are failed Invalid

Vacuum mode Long press SW6 “OK” button when the digital

display is not in menu selection state After running 8 hours Invalid

Power limitation mode Select power limitation mode 1 “n41” / Valid

Auto power save mode Select “nb3” / Valid

Auto snow-blowing mode 1 (2) Select “nb7” / Valid

VIP address setting / / Valid

oF / oC setting / / Valid

UP / DOWN system check button 2.2.4

Before pressing UP or DOWN button, allow the system to operate steadily for more than an hour. On pressing UP or DOWN

button, the parameters listed in Table 5-2.5 will be displayed in sequence.

Table 5-2.5: System check

DSP1 content

Parameters displayed on DSP2 Remarks

0.-- Unit address Master unit: 0; slave units: 1, 2, 3

1.-- Unit capacity Refer to Note 1

2.-- Number of outdoor units Displayed on master unit PCB only

3.-- Number of indoor units as set on PCB Displayed on master unit PCB only

4.-- Total capacity of outdoor unit Only available for master unit, displayed on slave units has no sense

5.-- Total capacity requirement of indoor units Displayed on master unit PCB only

6.-- Total corrected capacity requirement of indoor units Displayed on master unit PCB only

7.-- Operating mode Refer to Note 2

8.-- Outdoor unit actual operating capacity

9.-- Fan A speed index Refer to Note 3

10.-- Fan B speed index Refer to Note 3

11.-- Indoor heat exchanger pipe (T2/T2B) temperature (°C) Actual value = value displayed

12.-- Main heat exchanger pipe (T3) temperature (°C) Actual value = value displayed

13.-- Outdoor ambient (T4) temperature (°C) Actual value = value displayed

14.-- Plate heat exchanger cooling refrigerant inlet (T6A) temperature (°C) Actual value = value displayed

15.-- Plate heat exchanger cooling refrigerant outlet (T6B) temperature (°C) Actual value = value displayed

16.-- Inverter compressor A discharge temperature (°C) Actual value = value displayed

17.-- Inverter compressor B discharge temperature (°C) Actual value = value displayed

18.-- Inverter module A heatsink temperature (°C) Actual value = value displayed

19.-- Inverter module B heatsink temperature (°C) Actual value = value displayed

20.-- Plate heat exchanger cooling refrigerant outlet temperature minus inlet temperature (°C) Actual value = value displayed

21.-- Discharge superheat degree (°C) Actual value = value displayed

22.-- Inverter compressor A current (A) Actual value = value displayed

23.-- Inverter compressor B current (A) Actual value = value displayed

24.-- EXVA position Refer to Note 4

25.-- EXVB position Refer to Note 4

26.-- EXVC position Refer to Note 4

27.-- Compressor discharge pressure (MPa) Actual value = value displayed × 0.1

28.-- Reserved

29.-- Number of indoor units currently in communication with master unit Actual value = value displayed

30.-- Number of indoor units currently operating Displayed on master unit PCB only

31.-- Priority mode Refer to Note 5

32.-- Silent mode Refer to Note 6

33.-- Static pressure mode Refer to Note 7


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Table 5-2.5: System check (continued)

DSP1 content

Parameters displayed on DSP2 Remarks

34.-- Reserved

35.-- Reserved

36.-- DC voltage A Actual value = value displayed × 10

37.-- DC voltage B Actual value = value displayed × 10

38.-- Reserved

39.-- Address of VIP indoor unit

40.-- Reserved

41.-- Reserved

42.-- Refrigerant quantity Refer to Note 8

43.-- Reserved

44.-- Power mode Refer to Note 9

45.-- Most recent error or protection code “--“ is displayed if no error or protection events have occurred since start-up

-- -- -- End Notes:

1. Outdoor unit capacity setting: 0: 8HP; 1: 10HP; 2: 12HP; 3: 14HP; 4: 16HP; 5: 18HP; 6: 20HP; 7: 22HP; 8: 24HP; 9: 26HP; A: 28HP; B: 30HP; C: 32HP.

2. Operating mode: 0: off; 2: cooling; 3: heating; 4: forced cooling.

3. The fan speed index is related to the fan speed in rpm and can take any integer value in the range 1 (slowest) to 35 (fastest). 4. 480P: steps = value displayed × 4; 3000P: steps = value displayed × 24. 5. Priority mode:

0: auto priority; 1: cooling priority; 2: VIP priority or voting priority; 3: heating only; 4: cooling only. 6. Silent mode:

0: night silent time 6h/10h; 1: night silent time 6h/12h; 2: night silent time 8h/10h; 3: night silent time 8h/12h; 4: no silent mode; 5: silent mode 1; 6: silent mode 2; 7: silent mode 3; 8: super silent mode 1; 9: super silent mode 2; 10: super silent mode 3; 11: super silent mode 4.

7. Static pressure mode: 0: standard static pressure; 1: low static pressure; 2: medium static pressure; 3: high static pressure; 4: super high static pressure.

8. Refrigerant quantity: 0: normal; 1: slightly excessive; 2: significantly excessive; 3: slightly insufficient; 4: significantly insufficient; 5: critically insufficient.

9. Power mode: 0: 100% capacity output; 1: 90% capacity output; 2: 80% capacity output; 3: 70% capacity output; 4: 60% capacity output; 5: 50% capacity output; 6:

40% capacity output; 10: auto power save mode, 100% capacity output; 11: auto power save mode, 90% capacity output; 12: auto power save mode, 80% capacity output; 13: auto power save mode, 70% capacity output; 14: auto power save mode, 60% capacity output; 15: auto power save mode, 50% capacity output; 16: auto power save mode, 40% capacity output;

Digital display output 2.2.5

Table 5-2.6: Digital display output in different operating states

Outdoor unit state Parameters displayed on DSP1 Parameters displayed on DSP2

Standby Unit's address The number of indoor units in

communication with the outdoor units

Normal

operation

For single

compressor units --

Running speed of the compressor in

rotations per second

For dual

compressor units

Running speed of compressor B in


Running speed of compressor A in


Error or protection -- or placeholder Error or protection code

In menu mode Refer to Table 5-2.3 Refer to Table 5-2.3

System check Refer to Table 5-2.5 Refer to Table 5-2.5

DSP1

DSP2

V6 VRF 50Hz

65

Part 5

- Electrical C

om

po

ne

nts an

d W

iring D

iagrams

3 Compressor Inverter Module

Layout 3.1.1

Figure 5-3.1: Compressor inverter module components

LED indicators LED1 and LED2 3.1.2

Table 5-3.1: LED indicators LED1 and LED2

Indicator LED indicator function and status

LED 1 Inverter module operating indicator. Continuously on if the compressor is running normally and

flashing if an inverter module error has occurred1.

LED 2 Inverter module error indicator. Continuously on if an inverter module error has occurred1.

Note:

1. If an inverter module error occurs, refer to Part 6, “Xh4 Troubleshooting”. The error code is displayed on the digital display.

Dial switch S7 setting 3.1.3

Dial switch S7 is used to set compressor inverter module A/B address. The compressor inverter module A/B location refers

to the wiring diagram. S7 on inverter module Inverter module address

0 for compressor inverter module A

1 for compressor inverter module B

V6

66

Mid

ea V

6 Se

ries S

ervi

ce M

anua

l

4 W8-28Figur

VRF 50HWiring Dia8HP re 5‐4.1: 8‐28HP

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lack)

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P wiring diagra

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23

+~

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sw

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ule

heat

sink

tem

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sens

orCN

21(C

N22)

CN28

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FA

N B

CN84

CN45

CN67_1

CN66_1

CN85

CN83

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CN44

CN43

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CN66

0

A

CN72

EEVC

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VC

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B

ST

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EA

TB

HE

AT

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ATA

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CN82

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(Rig

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capa

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1

ON

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CN4)

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fa

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er in

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entio

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EN

C2

is f

acto

ry s

ettin

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do n

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e at

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E

NC

1 is

ava

ilabl

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mul

ti ou

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it sy

stem

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wat

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our

me

ter

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cont

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r

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run

its c

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bus

Res

erve

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door

uni

tad

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0

Mas

ter

unit

(Fac

tory

sett

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nnec

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diag

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is f

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efer

ence

onl

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leas

e re

fer

to t

he a

ctua

l pro

duct

.

me

ter

bus

30-3Figur

32HP re 5‐4.2: 30‐32H

N_

ou

tR

A

CN

4N

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ut

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CN

4CN10

CN

10

Red(Black)

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e

Red

Re

d

Whi

te

Red(B

lack)

HP wiring diagr

CN

5P

_o

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CN

3

N_in

CN

1P

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S7

CN

6

CN

7

CN

11

L1

L2

L3

CN

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CN

3

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CN

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CN

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1

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ack

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filt

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pres

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ompr

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ayo

ut

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wn

CN

8(C

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+

-~

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R1

T

TP

1-P

RO

TP

2-P

RO

C

L-P

RO

L3’

L1’

L2’

L3’

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FA

N A

CN

30

Red

White

Blu

e

Red

White

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lack

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Bl u

e

H-P

RO

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NA

/B

EE

VA

/EE

VB

/EE

VC

BR

1/B

R2

CO

MP

A/C

OM

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DC

Fan

Ele

ctro

nic

expa

nsio

n va

lve

Ck

ht

Inve

rter

com

pres

sor

A/B

CO

DE

NA

ME

Sin

gle-

phas

e B

ridge

Rec

tifie

r

L-PRO

CN19

H-PRO

CN18 DS

P1

DS

P2

CN17

H-YL1T7C1

OK

UP

ME

NU

DO

WN

EN

C3

S12

IN_

NU

M

TF

1

T7

C1

CN4

T7C2

CN5 CN8

T6A

C

T

T7

C2

CN1

T4 T3

CN3

TF2

CN3_1

TF

2

CN15

T6A

T4

T3

EN

C2

PO

WE

R

CN

12

CN

9C

N10

CN

11

CN

3N

P

CN

30

H-Y

L1

CN31

(CN3

2)

1

ON

23

+~

BR

2CN

32(C

N31)

EN

C1

NU

M_

S

(Left)

AC

filte

rb

oa

rd

Red

Blu

e

Blu

eBl

ack

DC

fa

n d

rive

bo

ard

A

ST

1

H-P

RO

/L-P

RO

H-Y

L1

RA

/RB

IC17

SV

2/S

V4-

SV

9

HE

ATA

/HE

AT

B

4-w

ay v

alve

Rea

ctan

ce

Cur

rent

sen

sor

Hig

h/Lo

w p

ress

ure

ON

/OF

F s

witc

h

Hig

h pr

essu

re s

enso

r

Cra

nkca

se h

eate

r

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d va

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nt s

enso

r

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CN8_1

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EE

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CN20

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EE

VA

T6

B

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NC

N5

CN

51

L1

L2

L3

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8

1

ON

23

4

CN1(

CN4)

-~

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filt

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ack

bo

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A

Mai

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1/T

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Pla

te h

eat

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ange

r co

olin

g re

frig

eran

tin

let/

outle

t te

mpe

ratu

re s

enso

r

Mai

n ex

chan

ger

pipe

tem

pera

ture

sens

or

T6A

/T6B

Out

door

am

bien

t te

mpe

ratu

re s

enso

r

Dis

char

ge t

empe

ratu

re s

enso

r

Inve

rter

-mod

ule

heat

sink

tem

pera

ture

sens

or

CN21

(CN2

2)

CN28

O-D

FA

N B

CN

CN

CN6

CN6

CN85

CN83

CN46

CN44

CN43

CN47

CN67

CN66

N70

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CN72

EEVC

EE

VC

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EE

VB

ST

1S

V4

SV

5S

V7

SV

8A

SV

9

SV

6S

V8B

HE

AT

B

HE

AT

BH

EA

TA

HE

ATA

CN30

CN82

N-ON

CN41

SV

2

(Rig

ht)

Red

Blac

kW

hite

Bl u

e

Re

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ack

Whi

teB

lue

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kBl

ack

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kBl

ack

capa

city

sett

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EN

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B

30H

P

C

32H

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Term

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FF

sw

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V

CN

3

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NP

ST

1

N84

N45

67_1

66_1

SV

4S

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SV

7S

V8A

SV

9

SV

6S

V8

B

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TA HEA

TAHEAT

B HEAT

B

AB

CX

T1

N

SV

2

1

ON

23

4SW1

DC

fa

n d

rive

bo

ard

B

Pow

erin

Att

entio

n：

EN

C2

isfa

ctor

yse

ttin

g，

dono

tch

ange

atw

ill；

CN4

CN6

To kilo

wat

t-To ce

ntra

li-ze

d

To indo

or u

nits

com

mun

i

To outd

oor

units

com

mR

eser

ved

Out

door

uni

tad

dres

sse

ttin

g

EN

C1

0

Mas

ter

unit

(Fac

tory

sett

ing)

12

EN

C1

NU

M_S

Sla

veun

it 1

Sla

veun

it 2

V6 VRF 50

16

02

70

00

00

75

28

Pow

er in

Att

entio

n：

EN

C2

is f

acto

ry s

ettin

g，

do n

ot c

hang

e at

will；

E

NC

1 is

ava

ilabl

e in

mul

ti ou

tdoo

r un

it sy

stem

.T

he d

otte

d fr

ame

sect

ion

is u

se b

y so

me

mod

els.

Thi

s co

nnec

tion

diag

ram

is f

or r

efer

ence

onl

y.P

leas

e re

fer

to t

he a

ctua

l pro

duct

.

hour

met

er

zed

cont

rolle

rco

mm

uni-

catio

nbu

s

units

com

m-

unic

atio

n bu

sR

eser

ved

0Hz

67

Part 5 - Electrical Components and W

iring Diagrams

V6 VRF 50Hz

68

Mid

ea

V6

Se

rie

s Se

rvic

e M

anu

al

V6 VRF 50Hz

69

Part 6

- Diagn

osis an

d Tro

ub

lesh

oo

ting

Part 6

Diagnosis and

Troubleshooting

1 Error Code Table .................................................................................... 70

2 Troubleshooting .................................................................................... 71

3 Appendix to Part 6 .............................................................................. 131

V6 VRF 50Hz

70

Mid

ea

V6

Se

rie

s Se

rvic

e M

anu

al

1 Error Code Table

Table 6-1.1: Error code table

Error

code1

Content Remarks Manual re-start

required2

E0 Communication error between outdoor units Only displayed on the slave unit

with the error No

E1 Phase sequence error Displayed on the unit with the error Yes

E2 Communication error between indoor and master unit Only displayed on the master unit No

E4 Outdoor heat exchanger temperature sensor (T3) error or

outdoor ambient temperature sensor (T4) error Displayed on the unit with the error No

E5 Abnormal power supply voltage Displayed on the unit with the error No

E7 Compressor top or discharge pipe temperature sensor (T7C1/2)

error Displayed on the unit with the error Yes

E8 Outdoor unit address error Displayed on the unit with the error Yes

xE9 EEPROM mismatch Displayed on the unit with the error Yes

xF1 DC bus voltage error Displayed on the unit with the error No

F3 Plate heat exchanger cooling refrigerant outlet temperature

sensor (T6B) error Displayed on the unit with the error No

F5 Plate heat exchanger cooling refrigerant inlet temperature sensor

(T6A) error Displayed on the unit with the error No

F6 Electronic expansion valve connection error Displayed on the unit with the error

Refer to Note 3 Yes

xH0 Communication error between main control chip and inverter

driver chip Displayed on the unit with the error No

H2 Number of slave units detected by master unit has decreased Only displayed on the master unit No

H3 Number of slave units detected by master unit has increased Only displayed on the master unit No

xH4 Inverter module protection Displayed on the unit with the error Yes

H5 P2 protection appears three times in 60 minutes Displayed on the unit with the error Yes

H6 P4 protection appears three times in 100 minutes Displayed on the unit with the error Yes

H7 Number of indoor units detected by master unit not same as

number set on main PCB Only displayed on the master unit No

H8 High pressure sensor error Displayed on the unit with the error No

H9 P9 protection appears ten times in 120 minutes Displayed on the unit with the error Yes

yHd Slave unit malfunction Only displayed on the master unit No

C7 PL protection appears three times in 100 minutes Displayed on the unit with the error Yes

P1 Discharge pipe high pressure protection Displayed on the unit with the error No

P2 Suction pipe low pressure protection Displayed on the unit with the error No

xP3 Compressor current protection Displayed on the unit with the error No

P4 Discharge temperature protection Displayed on the unit with the error No

P5 Outdoor heat exchanger temperature protection Displayed on the unit with the error No

P9 Fan module protection Displayed on the unit with the error No


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Table 6-1.1: Error code table (continued)

Error

code1

Content Remarks Manual re-start

required2

PL Inverter module temperature protection Displayed on the unit with the error No

PP Compressor discharge insufficient superheat protection Displayed on the unit with the error No

xL0 Inverter module protection Displayed on the unit with the error Yes

xL1 DC bus low voltage protection Displayed on the unit with the error Yes

xL2 DC bus high voltage protection Displayed on the unit with the error Yes

xL4 MCE error Displayed on the unit with the error Yes

xL5 Zero speed protection Displayed on the unit with the error Yes

xL7 Phase sequence error Displayed on the unit with the error Yes

xL8 Compressor frequency variation greater than 15Hz within one

second protection Displayed on the unit with the error Yes

xL9 Actual compressor frequency differs from target frequency by

more than 15Hz protection Displayed on the unit with the error Yes

Notes:

1. 'x' is a placeholder for the compressor system (compressor and related electrical components), with 1 representing compressor system A and 2

representing compressor system B. 'y' is a placeholder for the address (1 or 2) of the slave unit with the error.

2. For some error codes, a manual restart is required before the system can resume operation.

3. Once the EXV has been connected properly, the error code will flash to indicate that the connection has been re-established. A manual restart is then

required before the system can resume operation.

2 Troubleshooting

2.1 Warning

All electrical work must be carried out by competent and suitably qualified, certified and

accredited professionals and in accordance with all applicable legislation (all national, local and other laws,

standards, codes, rules, regulations and other legislation that apply in a given situation).

Power-off the outdoor units before connecting or disconnecting any connections or wiring, otherwise electric

shock (which can cause physical injury or death) may occur or damage to components may occur.

Warning

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2.2 E0: Communication error between outdoor units


Description 2.2.2

Communication error between outdoor units.

All units stop running.

Error code is only displayed on the slave unit with the error.

Trigger / recover condition 2.2.3

Trigger condition: Slave unit cannot receive signal from master unit for 60s.

Recover condition: Slave unit can receive signal from master unit.

Reset method: Resume automatically.

Possible causes 2.2.4

Incorrect outdoor unit address setting.

Communication wires between outdoor units not connected properly.

Loosened wiring within electric control box.

Damaged main PCB or electric control box communication terminals block.

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Procedure 2.2.5

E0

ODU addresses on switch ENC1 are set

incorrectly1 Yes Set the ODU addresses correctly

No

Communication wires between ODUs are

not connected properly2 Yes

Ensure the communication wires are

three-core shielded cable and are

connected properly

No

Wires between outdoor main PCB and

electric control box communication

terminals block are loose

Yes Ensure the wires are connected properly

No

Replacing outdoor main PCB resolves the

error

No

Replace electric control box

communication terminals block

Notes:

1. The master unit address should be set as 0, slave units addresses should be set from 1 to 3, and the addresses should not be repeated within one system. 2. All the wires for H1, H2, E connections should be three-core shielded cable, the wiring should be connected according to polarity (H1 to H1, etc), the wiring

should not be open or short circuited.

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2.3 E1: Phase sequence error


Description 2.3.2

Phase sequence error.


Error code is only displayed on the unit with the error.


Trigger condition: Wrong phase connection for 1.6s or phase missing for 48s.

Recover condition: Correct phase connection.

Reset method: Manually restart.


Power supply phases not connected in correct sequence.

Power supply terminals loose.

Power supply abnormal.

Main PCB damaged.

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Procedure 2.3.5

E1

The phase sequence of the 3-phase

power supply is incrorrect1

Yes Exchange any two of the 3 phase wires

No

Some power supply terminals are loose2 Yes Ensure all supply terminals are securely

fastened

No

The power supply is abnormal Yes Check the power supply equipment

No

Replace outdoor main PCB

Notes:

1. The A, B, C terminals of the 3-phase power supply should match compressor phase sequence requirements. If the phase sequence is inverted, the compressor will operate inversely. If the wiring connection of each outdoor unit is in A, B, C phase sequence, and multiple units are connected, the current difference between C phase and A, B phases will be very large as the power supply load of each outdoor unit will be on C phase. This can easily lead to

tripped circuits and terminal wiring burnout. Therefore if multiple units are to be used, the phase sequence should be staggered, so that the current is distributed among the three phases equally.

2. Loose power supply terminals can cause the compressors to operate abnormally and compressor current to be very large.

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2.4 E2: Communication error between indoor and master unit


Description 2.4.2

Communication error between indoor and master unit.


Error code is only displayed on the master unit.


Trigger condition: Indoor units and outdoor units cannot communication for 2 minutes after the system power on 20

minutes.

Recover condition: Communication go back to normal.



Communication wires between indoor and outdoor units not connected properly.

Indoor unit power supply abnormal.


Interference from high voltage wires or other sources of electromagnetic radiation.

Communication wire too long.


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Procedure 2.4.5

E2

Communication wires P Q E have short

circuited or disconnected1 Yes Reconnect the communication wires

No

Communication wires P Q E are not

connected in a daisy chain Yes Connect the communication wires in a

daisy chain

No

IDU power supply is abnormal Yes Ensure normal power supply

No

Wires between outdoor main PCB and

electric control box communication

terminals block are loose


No

Interference from high voltage (220V or

higher) wires Yes Ensure the communication wires and

high voltage wires are separated

No

Communication wires are close to a

source of electromagnetic radiation such

as transformer or strong fluorescent lamp

Yes Remove the source of interference, or

add additional shielding to the

communication wires

No

The length of communication wire is over

1200m Yes Reduce the wire length to less than

1200m or strengthen the signal

No

Replacing outdoor main PCB resolves the

error

No

Replace electric control box

communication terminals block

Notes:

1. Measure the resistance among P, Q and E. The normal resistance between P and Q is 120Ω, between P and E is infinite, between Q and E is infinite.

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2.5 E4: Temperature sensor (T3/T4) error


Description 2.5.2

Outdoor heat exchanger temperature sensor (T3) error or outdoor ambient temperature sensor (T4) error.




Trigger condition: The main control board cannot receive the feedback signal of temperature sensor T3 or T4.

Recover condition: The main control board can receive the feedback signal of temperature sensor T3 or T4.



Temperature sensor not connected properly or has malfunctioned.

Damaged main PCB.

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Procedure 2.5.5

E4

Temperature sensor connection on main

PCB is loose1 Yes Ensure the sensor is connected properly

No

Temperature sensor has short-circuited

or failed2 Yes Replace the sensor

No


Notes:

1. Outdoor ambient temperature sensor (T4) and heat exchanger temperature sensor (T3) connection is port CN1 on the main PCB (labeled 11 in Figure 5-2.1 in Part 5, 2.1 “Ports”).

2. Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor’s resistance characteristics table, the sensor has failed. Refer to Table 6-3.1 in Part 6, 3.1 “Temperature Sensor Resistance Characteristics”.

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2.6 E5: Abnormal power supply voltage


Description 2.6.2

Abnormal power supply voltage.




Trigger condition: Outdoor unit power supply phase voltage < 165V.

Recover condition: Outdoor unit power supply phase voltage is > 180V.



Outdoor unit power supply voltage is abnormal or a phase is missing.


High voltage circuit error.

Main PCB damaged.

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Procedure 2.6.5

E5

ODU power supply is abnormal or a

phase is missing1 Yes Provide normal power supply

No

Wires between outdoor main PCB, AC

filter boards and electric control box

power supply terminals are loose


No

High voltage circuit error has occurred,

such as the compressor has

malfunctioned2, the fan motor has

short-circuited3, or the inverter module

has short-circuited4

Yes Replace or repair the relevant parts

No


Notes:

1. The normal voltage between A and N, B and N, and C and N is 198-242V. 2. The normal resistances of the inverter compressor are 0.7-1.5Ω among U V W and infinite between each of U V W and ground. If any of the resistances

differ from these specifications, the compressor has malfunctioned.

3. The normal resistances of the fan motor coil among U V W are less than 10Ω. If a measured resistance is 0Ω, the fan motor has short-circuited. 4. Set a multi-meter to buzzer mode and test any two terminals of P N U V W of the inverter module. If the buzzer sounds, the inverter module has

short-circuited.

Figure 6-2.1: Inverter module terminals

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2.7 E7: Temperature sensor (T7C1/2) error


Description 2.7.2

A compressor top temperature sensor or discharge pipe temperature sensor (T7C1/2) error.




Trigger condition: Discharge pressure ≥ 3MPa and discharge temperature < 15oC for 2 minutes.

Recover condition: Discharge pressure and temperature go back to normal.




Damaged main PCB.

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Procedure 2.7.5

E7



No



No


Notes:

1. Compressor top temperature sensor and discharge pipe temperature sensor connections are ports CN4 and CN5 on the main PCB (labeled 3 and 4, respectively, in Figure 5-2.1 in Part 5, 2.1 “Ports”).


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2.8 E8: Outdoor unit address error


Description 2.8.2

Outdoor unit address error.




Trigger condition: Outdoor unit address is set more than 3.

Recover condition: Outdoor unit addresses are set from 0 to 3.



Invalid outdoor unit address.

Main PCB damaged.

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Procedure 2.8.5

E8

The ODU's address is not in the valid

range1 Yes Slave units addresses should be set from

1 to 3

No

Replace the outdoor main PCB

Notes:

1. The master unit address should be set as 0, slave units addresses should be set from 1 to 3, and the addresses should not be repeated within one system.

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2.9 xE9: EEPROM mismatch


In the error code, 'x' is a placeholder for the compressor system (compressor and related electrical components), with 1

representing compressor system A and 2 representing compressor system B.

Description 2.9.2

1E9 indicates a compressor A EEPROM mismatch.

2E9 indicates a compressor B EEPROM mismatch.




Trigger condition: Compressor drive parameter is mismatch.

Recover condition: Compressor drive parameter is match.



Outdoor unit was powered on immediately after being powered off.

Main PCB damaged.

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Procedure 2.9.5

xE9

The outdoor unit was powered on

immediately after being powered off1 Yes

Power off the unit and wait for the digital

display to turn off before restarting the

unit

No


Notes:

1. When performing a manual restart of an outdoor unit, once the unit has been powered off it should not be powered on again until the digital display has

turned off.

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2.10 xF1: DC bus voltage error


'x' is a placeholder for the compressor system (compressor and related electrical components), with 1 representing

compressor system A and 2 representing compressor system B.

Description 2.10.2

1F1 indicates compressor A DC bus voltage error; 2F1 indicates compressor B DC bus voltage error.




Trigger condition: DC bus voltage < 350V or DC bus voltage > 700V continuously for 10 seconds.

Recover condition: DC bus voltage goes back to normal.

Reset method: Restart automatically.


Loosened wiring of the compressor inverter module.

Incorrect wiring of the reactor and DC bus wire.

Abnormal power supply.

Inverter module damaged.

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Procedure 2.10.5

Note:

1. The DC bus wire should run from the N_in terminal on the inverter module, through the current sensor (in the direction indicated by the

arrow on the current sensor), and end at the N_out terminal on the inverter module.

Figure 6-2.2: DC detection wire connection method

F1 error

Compressor inverter module wiring is loosened

Reconnect cables based on wiring diagram

Reactor and DC bus wiring is incorrectly1

Reconnect the reactor and DC bus wire based on wiring

diagram

The power supply is abnormal

No

No

Yes

YesDisconnect the power supply

Check the power supply equipment

Yes

Replace the inverter module

No

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2.11 F3, F5: Temperature sensor (T6B/T6A) error


Description 2.11.2

F3 indicates plate heat exchanger cooling refrigerant outlet temperature sensor (T6B) error.

F5 indicates plate heat exchanger cooling refrigerant inlet temperature sensor (T6A) error.




Trigger condition: Temperature sensor T6A(B) is open or short-circuit.

Recover condition: Temperature sensor T6A(B) connection ports can detect load.




Damaged main PCB.

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Procedure 2.11.5

F3 / F5



No



No


Notes:

1. Plate heat exchanger cooling refrigerant inlet temperature sensor (T6A) and plate heat exchanger cooling refrigerant outlet temperature sensor (T6B) connection are port CN8 and CN8_1 on the main PCB (labeled 10 and 12, respectively, in Figure 5-2.1 in Part 5, 2.1 “Ports”).


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2.12 F6: Electronic expansion valve connection error


Description 2.12.2

Electronic expansion valve connection error.




Trigger condition: The main control board cannot receive the feedback signal of EXV.

Recover condition: The main control board can receive the feedback signal of EXV.

Reset method: When the main control board can receive the feedback signal of EXV, F6 flashes, a manual system

restart id required before the system can resume operation.


Electronic expansion valve coil not connected properly or has malfunctioned.

Damaged main PCB.

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Procedure 2.12.5

F6

Electronic expansion valve coil

connection on main PCB is loose1 Yes Ensure the sensor is connected properly

No

Electronic expansion valve coil has

malfunctioned2 Yes Replace the sensor

No


Notes:

1. Electronic expansion valve coil connections are port CN70, CN71 and CN72 on the main PCB (labeled 18, 19 and 20, respectively, in Figure 5-2.1 in Part 5, 2.1 “Ports”).

2. The normal resistances between EXV coil wiring terminals RED and white / yellow / orange / blue are 40-50Ω. If any of the resistances differ from the value, the EXV coil has malfunctioned.

Figure 6-2.3: EXV coil wiring terminals

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2.13 xH0: Communication error




Description 2.13.2

1H0 indicates a communication error between the main control chip and the compressor A inverter driver chip.

2H0 indicates a communication error between the main control chip and the compressor B inverter driver chip.




Trigger condition: Main control chip and inverter driver chip cannot communication for 2 minutes.

Recover condition: Communication go back to normal.



Incorrect compressor inverter module address setting.

Loosened communication wiring from the main PCB to

the inverter module.

Bridge rectifier damaged.

Main PCB damaged.

Compressor inverter module damaged.

Procedure 2.13.5

H0 error

Compressor inverter module address setting is incorrect

Reset the compressor inverter module address via

dial switch S7 on inverter module

1

Communication wire from outdoor main PCB CN26 to inverter module CN8/

CN9 is loosened2

Reconnect the communication wire

Both LED1 and LED2 on inverter module are off when power on

3

No

No

Yes

Yes

Check the power supply circuit

4Yes

Replace the outdoor main PCB, is the malfunction solved?

No

NormalYes

No


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Notes: 1. Compressor inverter module address is set through dial switch S7 on the inverter module. The compressor inverter module A/B location refers to the

wiring diagram.

S7 on inverter module Inverter module address



2. Communication wire from outdoor main PCB CN26 to inverter module CN8/CN9.

Communication port CN26 on main PCB Communication port CN8/CN9 on inverter module

3. LED1/2 on inverter module

4. Check the power supply for the compressor inverter module, port CN41 on filter board, the normal voltage should be DC310V; check the high pressure switch connection port CN61 on filter board, the normal resistance should be zero; Check the single phase bridge and fuse on filter board; check the connection cable from ODU main PCB port CN82 to filter board port CN30 which is DC310V power control port.

CN41 Power for

SMPS of

Compressor inverter

module

CN61 High

pressure switch

connection port

Fuse 30A CN30

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2.14 H2, H3: Slave units decreased/increased


Description 2.14.2

H2 indicates that the number of slave units detected by master unit has decreased.

H3 indicates that the number of slave units detected by master unit has increased.




Trigger condition: Number of slave units detected by master unit has decreased or increased.

Recover condition: Number of slave units detected by master unit goes back to normal.



Some outdoor units are powered off.


Incorrect outdoor unit address setting.

Communication wires between outdoor units not connected properly.



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Procedure 2.14.5

H2 / H3

Some outdoor units in the system are

powered off Yes Power on all the outdoor units

No


No

Troubleshoot as for an E0 error2

Notes:

1. See “E0 Troubleshooting”.

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2.15 xH4: Inverter module protection




Description 2.15.2

1H4 indicates compressor A inverter module protection.

2H4 indicates compressor B inverter module protection.




Trigger condition: Compressor appears three inverter module protections.

Recover condition: Inverter module goes back to normal.



Inverter module protection.

DC bus low or high voltage protection.

MCE error.

Zero speed protection.

Phase sequence error.

Excessive compressor frequency variation.

Actual compressor frequency differs from target frequency.

Specific error codes for xH4 inverter module protection 2.15.5

If an xH4 error code is displayed, enter menu mode “n31” (refer to Part 5, 2.2.3 “menu mode”) to check the history error

code to check the following specific error code: xL0, xL1, xL2, xL4, xL5, xL7, xL8, xL9.

Table 6-2.1: Specific error codes for error xH4

Specific error code1 Content

xL0 Inverter module protection

xL1 DC bus low voltage protection

xL2 DC bus high voltage protection

xL4 MCE error

xL5 Zero speed protection

xL7 Phase sequence error

xL8 Compressor frequency variation greater than 15Hz within one second protection

xL9 Actual compressor frequency differs from target frequency by more than 15Hz protection

Notes: 1. 'x' is a placeholder for the compressor system (compressor and related electrical components), with 1 representing compressor system A and

2 representing compressor system B.

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The specific error codes xL0, xL1, xL2 and xL4 can also be obtained from the inverter module LED indicators. If an inverter

module error has occurred, LED2 is continuously on and LED1 flashes.

Figure 6-2.4: LED indicators LED1 and LED2 on inverter module

Table 5-3.2: Errors indicated on LED1

LED1 flashing pattern Corresponding error

Flashes 8 times and stops for 1 second, then repeats xL0 - Inverter module protection

Flashes 9 times and stops for 1 second, then repeats xL1 - DC bus low voltage protection

Flashes 10 times and stops for 1 second, then repeats xL2 - DC bus high voltage protection

Flashes 12 times and stops for 1 second, then repeats xL4 - MCE error

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L0: Inverter module protection 2.15.6

Note:

2. The DC bus wire should run from the N_in terminal on the inverter module, through the current sensor (in the direction indicated by the

arrow on the current sensor), and end at the N_out terminal on the inverter module.

Figure 6-2.5: DC detection wire connection method

L0 protection

The DC bus wire connected incorrectly1 Ensure the wire is

connected properly

The compressor wiring is connected incorrectly

Reconnect the cables based on wiring diagram

Replace the compressor

The inverter module is not well heat dissipation

The IPM screws is loosenFasten IPM screws again

The silica gel is coated not well for heat radiation

Coat with silica gel

The compressor has less than 12 hours preheating before initial operating

Switch on power again to detect whether the compressor can start

Refer to “P3 over current protection”


Ensure enough preheating time

No

No

No

No

No

No

Yes

Yes

Yes

Yes

Yes

Yes

Yes

No

Yes

Yes

No

No

Disconnectthe powersupply

The resistance between 3 phases of compressor is over 5Ω

The insulation resistance of compressor is less than 100kΩ

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L1: DC bus low voltage protection 2.15.7

Note:

1. The normal DC voltage between terminals P and N on inverter module should be 450-650V. When the voltage is lower than 350V, L1

protection will be appeared.


L1 protection

The power supply is abnormalCheck the power supply

equipment

No output from bridge rectifier


No

No

No

Yes

Yes

Yes

Yes

The DC bus voltage (P, N) is abnormal1

The reactor performs wellReplace the

reactorNo

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L2: DC bus high voltage protection 2.15.8

Note:

1. The normal DC voltage between terminals P and N on inverter module should be 450-650V. When the voltage is higher than 700V, L2

protection will be appeared.


L2 protection

The power supply is abnormalCheck the power supply

equipment

The DC bus voltage (P, N) is abnormal1 Replace the 3-phase bridge

rectifier


No

No

Yes

Yes

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L4: MCE error 2.15.9

Notes: 1. Compressor inverter module address is set through dial switch S7 on the inverter module. The compressor inverter module A/B location refers to the

wiring diagram.

S7 on inverter module Inverter module address



L4 protection

ODU ventilation is not goodRemove barriers from heat

exchanger and air outlet of ODU

ODU stop valves are closed Open the ODU stop valves




The insulation resistance of compressor is less than 100Ω

Replace the compressor inverter board, restart the unit and the error is

solved

Refer to P1 or P3 troubleshooting

No

No

Yes

Yes

Disconnectthe powersupply

Compressor wiring is not properly

Inverter module address setting1 and

discharge temperature sensor wiring is not properly

Reset the inverter module address and reconnect the discharge temperature sensor cables

YesNormal

Yes

Yes

Yes

Yes

No

No

No

No

No

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L7: Phase sequence error 2.15.10

L7 protection

Compressor wiring is looseReconnect cables based on

wiring diagram

An open circuit in the 3-phase U/V/W of compressor terminals



No

No

Yes

YesDisconnect the power supply

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L8: Compressor frequency variation greater than 15Hz within one second protection 2.15.11

L9: Actual compressor frequency differs from target frequency by more than 15Hz protection

L8 protection

ODU stop valves are closed Open the ODU stop valves




The insulation resistance of compressor is less than 100Ω

Replace the compressor inverter board, restart the unit and the error is

solved

Refer to P1 or P3 troubleshooting

No

Yes

Disconnect the power supply

Compressor wiring is not properly

YesNormal

Yes

Yes

Yes

No

No

No

No

L9 protection

The compressor has less than 12 hours preheating before initial operating

Ensure enough preheating timeYes

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Compressor replacement procedure 2.15.12

Step 1: Remove faulty compressor and remove oil

Remove the faulty compressor from the outdoor unit.

Before removing the oil, shake the compressor so as to not allow

impurities to remain settled at the bottom.

Drain the oil out of the compressor and retain it for inspection.

Normally the oil can be drained out from the compressor discharge

pipe.

Step 2: Inspect oil from faulty compressor

The oil should be clear and transparent. Slightly yellow oil is not an indication of any problems. However, if the oil is

dark, black or contains impurities, the system has problems and the oil needs to be changed. Refer to Figure 5-4.16

for further details regarding inspecting compressor oil. (If the compressor oil has been spoiled, the compressor will

not be being lubricated effectively. The scroll plate, crankshaft and bearings will wear. Abrasion will lead to a larger

load and higher current. More electric energy will get dissipated as heat and the temperature of the motor will

become increasingly high. Finally, compressor damage or burnout will result.)

Step 3: Check oil in other compressors in the system

If the oil drained from the faulty compressor is clean, go to Step 6.

If the oil drained from the faulty compressor is only lightly spoiled, go to Step 4.

If the oil drained from the faulty compressor is heavily spoiled, check the oil in the other compressors in the system.

Drain the oil from any compressors where the oil has been spoiled. Go to Step 4.

Step 4: Replace oil separator(s) and accumulator(s)

If the oil from a compressor is spoiled (lightly or heavily), drain the oil from the oil separator and accumulator in that

unit and then replace them.

Step 5: Check filters(s)

If the oil from a compressor is spoiled (lightly or heavily), check the filter between the gas stop valve and the 4-way

valve in that unit. If it is blocked, clean with nitrogen or replace.

Step 6: Replace the faulty compressor and re-fit the other compressors

Replace the faulty compressor.

If the oil had been spoiled and was drained from the non-faulty compressors

in Step 3, use clean oil to clean them before re-fitting them into the units. To

clean, add oil into the compressor through the discharge pipe using a funnel,

shake the compressor, and then drain the oil. Repeat several times and then

re-fit the compressors into the units. (The discharge pipe is connected to the

oil pool of the compressor by the inner oil balance pipe.)

Step 7: Add compressor oil

Add 1.2L of oil to the new compressor through the discharge pipe, using a

funnel.

Add 1.2L of oil to each of the compressors from which oil was drained in Step 3.

Only use FV68H oil. Different compressors require different types of oil. Using the wrong type of oil leads to various

problems.

Add additional oil to the accumulators such that the total amount of oil is 5L in 8-12HP units, 6L in 14-16HP units 7L in

18-22HP units, 9L in 24-28HP units and 10L in 30-32HP units.

Figure 6-2.8: Draining oil from a compressor

Figure 6-2.9: Compressor piping

Discharge pipe

Inner oilbalance

pipe

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Step 8: Vacuum drying and refrigerant charging

Once all the compressors and other components have been fully connected, vacuum dry the system and recharge

refrigerant. Refer to the V6 Engineering Data Book, Part 3.

Figure 6-2.10: Inspecting compressor oil

This oil is black

- it has been

carbonized

This oil is a little

yellow, but is clear

and transparent and

the condition is

acceptable

This oil is still

transparent but there

are impurities which

may clog the filter Cloudy or gray

oil indicates

abnormal

system

operation This oil contains

particles of copper

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Figure 6-2.11: Effects of spoiled compressor oil

Worn scroll plate

Worn scroll plate

Normal compressor

bearings

Seriously worn and

damaged bearings

Filter blocked by impurities,

which leads to abnormal

compressor suction

Worn crankshaft

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2.16 H7: Unmatched total number of indoor units


Description 2.16.2

Number of indoor units detected by master unit not same as number set on main PCB.




Trigger condition: Only one indoor unit cannot be detected by master unit for 8 hours or more than one indoor unit

cannot be detected by master unit for 3 minutes.

Recover condition: Number of indoor units detected by master unit is same as number set on main PCB.



Number of indoor units set on main PCB not same as actual number of indoor units.

Some indoor units are powered off.

Communication wires between indoor and outdoor units not connected properly.

Indoor unit PCB damaged.

Indoor unit without address or indoor unit address duplicated.

Main PCB damaged.

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Procedure 2.16.5

H7

Number of indoor units set on main PCB

not same as actual number of indoor

units1

Yes Change the setting on the PCB to be the

same as the actual number of indoor

units

No

Some indoor units are powered off Yes Power on all indoor units

No

After re-starting the ODUs and IDUs and

then waiting 2 minutes, an IDU displays

an E1 or FE error2

Yes Refer to indoor unit troubleshooting

guide. Resolving the indoor unit error

resolves the outdoor unit error

No

Two or more indoor units are assigned

the same address3 No

Yes

Setting the indoor units’ addresses

uniquely resolves the error No Replace outdoor main PCB

Notes:

1. The number of indoor units can be set on switches EN3 and S12 on the main PCB. 2. Indoor unit error code E1 indicates a communication error between indoor and master unit. Indoor unit error code FE indicates that an indoor unit has not

been assigned an address. 3. Indoor unit addresses can be checked and manually assigned using indoor unit remote/wired controllers. Alternatively, indoor unit addresses can be

automatically assigned by the master outdoor unit.

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2.17 H8: High pressure sensor error


Description 2.17.2

High pressure sensor error.




Trigger condition: Discharge pressure ≤ 0.3MPa.

Recover condition: Discharge pressure > 0.3MPa.



Outdoor unit stop valves are closed.

Pressure sensor not connected properly or has malfunctioned.

Insufficient refrigerant.

Low pressure side blockage.

Poor evaporator heat exchange.

Main PCB damaged.

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Procedure 2.17.5

H8

ODU stop valves are closed Yes Open the stop valves

No

High pressure sensor connection on main


No

High pressure sensor has short-circuited


No

Insufficient refrigerant caused by

refrigerant leakage3 Yes Add refrigerant and inspect system for

leaks

No

The low pressure side is blocked, caused

by crushed or bent pipe, closed EXV or

dirty filter4

Yes Inspect the system and fix the error. If the

filter is blocked by ice, the piping should

be cleaned

No

The evaporator heat exchange is poor5 Yes Inspect the system and fix the error

No

Replace the outdoor main PCB

Notes:

1. High pressure sensor connection is port CN17 on the main PCB (labeled 7 in Figure 5-2.1 in Part 5, 2.1 “Ports”). 2. Measure the resistance among the three terminals of the pressure sensor. If the resistance is of the order of mega Ohms or infinite, the pressure sensor

has failed.

3. An insufficiency of refrigerant causes compressor discharge temperature to be higher than normal, discharge and suction pressures to be lower than normal and compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. These issues disappear once sufficient refrigerant has been charged into the system. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of

Refrigerant System”. 4. A low pressure side blockage causes compressor discharge temperature to be higher than normal, suction pressure to be lower than normal and

compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. For normal system parameters refer to Table 6-3.4 and

6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”. 5. In cooling mode check indoor heat exchangers, fans and air outlets for dirt/blockages. In heating mode check outdoor heat exchangers, fans and air outlets

for dirt/blockages.

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2.18 yHd: Slave unit malfunction


In the error code, 'y' is a placeholder for the address (1, 2 or 3) of the slave unit with the error.

Description 2.18.2

1Hd indicates an error on the slave unit with address 1.






Trigger condition: Slave unit is malfunction.

Recover condition: Slave unit goes back to normal.



Slave unit malfunction.

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Procedure 2.18.5

yHd

Check relevant slave unit

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2.19 P1: Discharge pipe high pressure protection


Description 2.19.2

Discharge pipe high pressure protection. If the system has a 3-phase protector and the 3-phase protector is connected

with the high pressure switch, the system will display P1 protection when initially powered on, and P1 protection will

disappear once the system reaches a steady state.




Trigger condition: Discharge pressure ≥ 4.4MPa.

Recover condition: Discharge pressure ≤ 3.2MPa.




Pressure sensor/switch not connected properly or has malfunctioned.

Excess refrigerant.

System contains air or nitrogen.

High pressure side blockage.

Poor condenser heat exchange.

Main PCB damaged.

Procedure 2.19.5

P1


No

High pressure sensor connection on main


No

High pressure sensor has short-circuited


No

Flowchart continued on next page …

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… flowchart continued from previous page

Excess refrigerant3 Yes Discharge part of the refrigerant. Add oil

if it leaks during discharge

No

System contains air or nitrogen4 Yes Flush all refrigerant then vacuum the

system and recharge the refrigerant. Add

oil to the system if it leaks

No

The high pressure side is blocked, caused

by crushed or bent pipe or blocked EXV5 Yes Inspect the system and fix the error

No

The condenser heat exchange is poor6 Yes Inspect the system and fix the error

No


Notes:

1. The high pressure sensor connection is port CN17 on the main PCB (labeled 7 in Figure 5-2.1 in Part 5, 2.1 “Ports”). 2. Measure the resistance among the three terminals of the pressure sensor. If the resistance is of the order of mega Ohms or infinite, the pressure sensor

has failed. 3. Excess refrigerant causes discharge temperature to be lower than normal, discharge pressure to be higher than normal and suction pressure to be higher

than normal. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”.

4. Air or nitrogen in the system causes discharge temperature to be higher than normal, discharge pressure to be higher than normal, compressor current to be higher than normal, abnormal compressor noise and an unsteady pressure meter reading. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”.

5. High pressure side blockage causes discharge temperature to be higher than normal, discharge pressure to be higher than normal and suction pressure to be lower than normal. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”.

6. In cooling mode check outdoor heat exchangers, fans and air outlets for dirt/blockages. In heating mode check indoor heat exchangers, fans and air outlets

for dirt/blockages.

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2.20 P2, H5: Suction pipe low pressure protection


Description 2.20.2

Suction pipe low pressure protection. If the system has a 3-phase protector and the 3-phase protector is connected to

the low pressure switch, the system will display P2 protection when initially powered on, and P2 protection will

disappear once the system reaches a steady state.




Trigger condition:

For P2 protection: Suction pressure ≤ 0.05MPa.

For H5 protection: P2 protection appears three times in 60 minutes.

Recover condition: Suction pressure ≥ 0.15MPa.

Reset method:

For P2 protection: Resume automatically.

For H5 protection: Manually restart.




Low pressure side blockage.

Poor evaporator heat exchange.

Main PCB damaged.

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Procedure 2.20.5

P2 / H5


No


refrigerant leakage1 Yes Add refrigerant or inspect the system for

leaks

No

The low pressure side is blocked, caused

by crushed or bent pipe, blocked EXV, or

dirty filter2

Yes Inspect the system and fix the error. If the


be cleaned

No

The evaporator heat exchange is poor5 Yes Inspect the system and fix the error

No


Notes:

1. An insufficiency of refrigerant causes compressor discharge temperature to be higher than normal, discharge and suction pressures to be lower than normal and compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. These issues disappear once sufficient refrigerant has been charged into the system. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of

Refrigerant System”. 2. A low pressure side blockage causes compressor discharge temperature to be higher than normal, suction pressure to be lower than normal and

compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. For normal system parameters refer to Table 6-3.4 and

6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”. 3. In cooling mode check indoor heat exchangers, fans and air outlets for dirt/blockages. In heating mode check outdoor heat exchangers, fans and air outlets

for dirt/blockages.

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2.21 xP3: Compressor current protection




Description 2.21.2

1P3 indicates current protection on compressor A; 2P3 indicates current protection on compressor B.




Trigger condition: Current of compressor AA55PHDG –D1YG ≥ 24.6A or DC80PHDG –D1YG ≥ 33A.

Recover condition: Current of compressor AA55PHDG –D1YG < 24.6A or DC80PHDG –D1YG < 33A.




Indoor load too large.


Sudden interruption of power to IDUs.

Excess refrigerant.




Inverter module damaged.

Compressor damaged.

Main PCB damaged.

Procedure 2.21.5

xP3


No

The indoor load is too large1 Yes Make sure the combination ratio is less

than 130%

No


No

Sudden interruption of power to IDUs Yes Inspect the system and fix the error

No Flowchart continued on next page …

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No


system and recharge refrigerant. Add oil

to the system if it leaks

No


No



No

Inverter module has short-circuited6 Yes Replace the inverter module

No

Compressor has malfunctioned7 Yes Replace the compressor

No


Notes:

1. An indoor load that is too large causes suction and discharge temperatures to be higher than normal. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”.

2. Excess refrigerant causes discharge temperature to be lower than normal, discharge pressure to be higher than normal and suction pressure to be higher

than normal. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”. 3. Air or nitrogen in the system causes discharge temperature to be higher than normal, discharge pressure to be higher than normal, compressor current to

be higher than normal, abnormal compressor noise and an unsteady pressure meter reading. For normal system parameters refer to Table 6-3.4 and 6-3.5

in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”. 4. In cooling mode check outdoor heat exchangers, fans and air outlets for dirt/blockages. In heating mode check indoor heat exchangers, fans and air outlets

for dirt/blockages.


6. Set a multi-meter to buzzer mode and test any two terminals of P N U V W of the inverter module. If the buzzer sounds, the inverter module has

short-circuited. 7. The normal resistances of the inverter compressor are 0.7-1.5Ω among U V W and infinite between each of U V W and ground. If any of the resistances

differ from these specifications, the compressor has malfunctioned.

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2.22 P4, H6: Discharge temperature protection


;

Description 2.22.2

Discharge temperature protection.




Trigger condition:

For P4 protection: Discharge temperature (T7C1/2) ≥ 120oC.

For H6 protection: P4 protection appears three times in 100 minutes.

Recover condition: Discharge temperature (T7C1/2) ≤ 90 oC.

Reset method:

For P4 protection: Resume automatically.

For H6 protection: Manually restart.



Temperature sensor/switch not connected

properly or has malfunctioned.


System blockage.




Main PCB damaged.

Procedure 2.22.5

P4 / H6


No

Compressor top temperature sensor,

discharge pipe temperature sensor

and/or discharge temperature switch

connections on main PCB are loose1

Yes Ensure the sensors and switch are

connected properly

No

Compressor top temperature sensor

and/or discharge pipe temperature

sensor have short circuited or failed2

Yes Replace the faulty sensor(s)



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refrigerant leakage3 Yes Add refrigerant and inspect the system

for leaks

No

The system is blocked, caused by crushed

or bent pipe, blocked EXV or dirty filter4 Yes

Inspect the system and fix the error. If the


be cleaned

No


than 130%

No


system and recharge refrigerant. Add oil

to the system if it leaks

No


No


Notes:

1. Compressor top temperature sensor and discharge pipe temperature sensor connections are ports CN4 and CN5 on the main PCB (labeled 3 and 4,

respectively, in Figure 5-2.1 in Part 5, 2.1 “Ports”). The discharge temperature switch connection is port CN19 on the main PCB (labeled 2 in Figure 5-2.1 in Part 5, 2.1 “Ports”).

2. Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor’s resistance

characteristics table, the sensor has failed. Refer to Table 6-3.2 in Part 6, 3.1 “Temperature Sensor Resistance Characteristics”. 3. An insufficiency of refrigerant causes compressor discharge temperature to be higher than normal, discharge and suction pressures to be lower than

normal and compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. These issues disappear once sufficient

refrigerant has been charged into the system. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”.

4. A low pressure side blockage causes compressor discharge temperature to be higher than normal, suction pressure to be lower than normal and

compressor current to be lower than normal, and may cause frosting to occur on the suction pipe. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”.

5. An indoor load that is too large causes suction and discharge temperatures to be higher than normal. For normal system parameters refer to Table 6-3.4

and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”. 6. Air or nitrogen in the system causes discharge temperature to be higher than normal, discharge pressure to be higher than normal, compressor current to



for dirt/blockages.

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2.23 P5: Outdoor heat exchanger temperature protection


Description 2.23.2

Outdoor heat exchanger temperature protection.




Trigger condition: Outdoor heat exchanger temperature (T3) ≥ 65oC.

Recover condition: Outdoor heat exchanger temperature (T3) < 55 oC.









Main PCB damaged.

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Procedure 2.23.5

P5


No

Outdoor heat exchanger temperature

sensor connection on main PCB is loose1 Yes Ensure the sensor is connected properly

No

Outdoor heat exchanger temperature

sensor has short-circuited or failed2 Yes Replace the sensor

No


than 130%

No


system and recharge the refrigerant. Add

oil to the system if it leaks

No


No



No


Notes:

1. Outdoor heat exchanger temperature sensor connection is port CN1 on the main PCB (labeled 11 in Figure 5-2.1 in Part 5, 2.1 “Ports”).

2. Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor’s resistance characteristics table, the sensor has failed. Refer to Table 6-3.1 in Part 6, 3.1 “Temperature Sensor Resistance Characteristics”

3. An indoor load that is too large causes suction and discharge temperatures to be higher than normal. For normal system parameters refer to Table 6-3.4

and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”. 4. Air or nitrogen in the system causes discharge temperature to be higher than normal, discharge pressure to be higher than normal, compressor current to



for dirt/blockages.


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2.24 P9, H9: Fan module protection


;

Description 2.24.2

Fan module protection.




Trigger condition:

For P9 protection: Fan speed is too low.

For H9 protection: P9 protection appears ten times in 120 minutes.

Recover condition: Fan speed go back to normal.

Reset method:

For P9 protection: Resume automatically; For H9 protection: Manually restart.


Switch ENC2 incorrectly set.

Power or communication wires not connected properly.

Fan motor blocked or has failed.


AC filter board damaged.

Fan module damaged.

Main PCB damaged.

Procedure 2.24.5

P9 / H9

The capacity set on switch ENC2 on the

main PCB and the capacity given on the

unit’s nameplate do not match

Ensure the setting on switch ENC2

matches the unit capacity given on the

unit’s nameplate

No

Some power wires or communication

wires of fan module are not connected

properly

Yes Ensure power and communication wires

are connected properly

No

The fan motor is blocked or has failed Yes Remove obstruction or replace the fan

motor


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No

Voltage between P and N on fan module

is abnormal1 Yes Replace AC filter board

No

Replacing the fan module resolves the

error

No


Notes:

1. The normal voltage between P and N on the fan module is 310V DC.

Figure 6-2.12: Fan module P N terminals

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2.25 PL, C7: Inverter module temperature protection




Description 2.25.2

1PL indicates inverter module A temperature protection.

2PL indicates inverter module B temperature protection.




Trigger condition:

For PL protection: Inverter module heat sink temperature (TF1/2) ≥ 80oC.

For C7 protection: PL protection appears three times in 100 minutes.

Recover condition: Inverter module heat sink temperature (TF1/2) < 65oC

Reset method:

For PL protection: Resume automatically.

For C7 protection: Manually restart.


Blocked, dirty or loose heat sink.


Main PCB damaged.

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Procedure 2.25.5

PL / C7

The inverter module heat sink is blocked

or dirty Yes Clean or replace the heat sink

No

The screws connecting the heat sink to

the inverter module are loose Yes Tighten the screws and make sure the

heat sink is well-connected

No

Inverter module temperature sensor

connection on main PCB is loose1 Yes Ensure the sensor is connected properly

No

Inverter module temperature sensor has

short circuited or failed2 Yes Replace the sensor

No


Notes:

1. Inverter module temperature sensor connection is port CN3 and CN3_1 on the main PCB (labeled 5 and 6, respectively, in Figure 5-2.1 in Part 5, 2.1 “Ports”).


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2.26 PP: Compressor discharge insufficient superheat protection


Description 2.26.2

Compressor discharge insufficient superheat protection.




Trigger condition: Discharge gas superheat is ≤ 0oC for 20 minutes or ≤ 5oC for 60 minutes.

Recover condition: Discharge gas superheat go back to normal value.




Poor temperature sensor heat insulation.

Excess refrigerant.

Discharge pressure too high.

Main PCB damaged.

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Procedure 2.26.5

PP



sensor connections on main PCB are

loose1

Yes Ensure the sensors are connected

properly

No



sensor have short circuited or failed2

Yes Replace the faulty sensor(s)

No

Poor heat insulation of compressor top

temperature sensor resulting in

temperature reading lower than actual

temperature

Yes Ensure sufficient heat insulation for

compressor top temperature senor

No



No

Discharge pressure is too high Yes Troubleshoot as for a P1 error4

No


Notes:

1. Compressor top temperature sensor and discharge pipe temperature sensor connections are ports CN4 and CN5 on the main PCB (labeled 3 and 4, respectively, in Figure 5-2.1 in Part 5, 2.1 “Ports”).


3. Excess refrigerant causes discharge temperature to be lower than normal, discharge pressure to be higher than normal and suction pressure to be higher

than normal. For normal system parameters refer to Table 6-3.4 and 6-3.5 in Part 6, 3.2 “Normal Operating Parameters of Refrigerant System”. 4. See “P1 Troubleshooting”.

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3 Appendix to Part 6

3.1 Temperature Sensor Resistance Characteristics Table 6-3.1: Outdoor ambient temperature sensor and outdoor heat exchanger temperature sensor resistance characteristics

Temperature

(°C)

Resistance

(kΩ)

Temperature

(°C)

Resistance

(kΩ)

Temperature

(°C)

Resistance

(kΩ)

Temperature

(°C)

Resistance

(kΩ)

-20 115.3 20 12.64 60 2.358 100 0.6297

-19 108.1 21 12.06 61 2.272 101 0.6115

-18 101.5 22 11.50 62 2.191 102 0.5939

-17 96.34 23 10.97 63 2.112 103 0.5768

-16 89.59 24 10.47 64 2.037 104 0.5604

-15 84.22 25 10.00 65 1.965 105 0.5445

-14 79.31 26 9.551 66 1.896 106 0.5291

-13 74.54 27 9.124 67 1.830 107 0.5143

-12 70.17 28 8.720 68 1.766 108 0.4999

-11 66.09 29 8.336 69 1.705 109 0.4860

-10 62.28 30 7.971 70 1.647 110 0.4726

-9 58.71 31 7.624 71 1.591 111 0.4596

-8 56.37 32 7.295 72 1.537 112 0.4470

-7 52.24 33 6.981 73 1.485 113 0.4348

-6 49.32 34 6.684 74 1.435 114 0.4230

-5 46.57 35 6.400 75 1.387 115 0.4116

-4 44.00 36 6.131 76 1.341 116 0.4006

-3 41.59 37 5.874 77 1.291 117 0.3899

-2 39.82 38 5.630 78 1.254 118 0.3796

-1 37.20 39 5.397 79 1.2133 119 0.3695

0 35.20 40 5.175 80 1.174 120 0.3598

1 33.33 41 4.964 81 1.136 121 0.3504

2 31.56 42 4.763 82 1.100 122 0.3413

3 29.91 43 4.571 83 1.064 123 0.3325

4 28.35 44 4.387 84 1.031 124 0.3239

5 26.88 45 4.213 85 0.9982 125 0.3156

6 25.50 46 4.046 86 0.9668 126 0.3075

7 24.19 47 3.887 87 0.9366 127 0.2997

8 22.57 48 3.735 88 0.9075 128 0.2922

9 21.81 49 3.590 89 0.8795 129 0.2848

10 20.72 50 3.451 90 0.8525 130 0.2777

11 19.69 51 3.318 91 0.8264 131 0.2708

12 18.72 52 3.192 92 0.8013 132 0.2641

13 17.80 53 3.071 93 0.7771 133 0.2576

14 16.93 54 2.959 94 0.7537 134 0.2513

15 16.12 55 2.844 95 0.7312 135 0.2451

16 15.34 56 2.738 96 0.7094 136 0.2392

17 14.62 57 2.637 97 0.6884 137 0.2334

18 13.92 58 2.540 98 0.6682 138 0.2278

19 13.26 59 2.447 99 0.6486 139 0.2223

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Table 6-3.2: Compressor top temperature sensor and discharge pipe temperature sensor resistance characteristics

Temperature

(°C)

Resistance (kΩ)

Temperature

(°C)

Resistance (kΩ)

Temperature

(°C)

Resistance (kΩ)

Temperature

(°C)

Resistance (kΩ)

-20 542.7 20 68.66 60 13.59 100 3.702

-19 511.9 21 65.62 61 13.11 101 3.595

-18 483.0 22 62.73 62 12.65 102 3.492

-17 455.9 23 59.98 63 12.21 103 3.392

-16 430.5 24 57.37 64 11.79 104 3.296

-15 406.7 25 54.89 65 11.38 105 3.203

-14 384.3 26 52.53 66 10.99 106 3.113

-13 363.3 27 50.28 67 10.61 107 3.025

-12 343.6 28 48.14 68 10.25 108 2.941

-11 325.1 29 46.11 69 9.902 109 2.860

-10 307.7 30 44.17 70 9.569 110 2.781

-9 291.3 31 42.33 71 9.248 111 2.704

-8 275.9 32 40.57 72 8.940 112 2.630

-7 261.4 33 38.89 73 8.643 113 2.559

-6 247.8 34 37.30 74 8.358 114 2.489

-5 234.9 35 35.78 75 8.084 115 2.422

-4 222.8 36 34.32 76 7.820 116 2.357

-3 211.4 37 32.94 77 7.566 117 2.294

-2 200.7 38 31.62 78 7.321 118 2.233

-1 190.5 39 30.36 79 7.086 119 2.174

0 180.9 40 29.15 80 6.859 120 2.117

1 171.9 41 28.00 81 6.641 121 2.061

2 163.3 42 26.90 82 6.430 122 2.007

3 155.2 43 25.86 83 6.228 123 1.955

4 147.6 44 24.85 84 6.033 124 1.905

5 140.4 45 23.89 85 5.844 125 1.856

6 133.5 46 22.89 86 5.663 126 1.808

7 127.1 47 22.10 87 5.488 127 1.762

8 121.0 48 21.26 88 5.320 128 1.717

9 115.2 49 20.46 89 5.157 129 1.674

10 109.8 50 19.69 90 5.000 130 1.632

11 104.6 51 18.96 91 4.849

12 99.69 52 18.26 92 4.703

13 95.05 53 17.58 93 4.562

14 90.66 54 16.94 94 4.426

15 86.49 55 16.32 95 4.294

16 82.54 56 15.73 96 4.167

17 78.79 57 15.16 97 4.045

18 75.24 58 14.62 98 3.927

19 71.86 59 14.09 99 3.812

V6 VRF 50Hz

133

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Table 6-3.3: Inverter module temperature sensor resistance characteristics

Temperature

(°C)

Resistance (kΩ)

Temperature

(°C)

Resistance (kΩ)

Temperature

(°C)

Resistance (kΩ)

Temperature

(°C)

Resistance (kΩ)

-30 971.4 10 109.0 50 19.70 90 5.000

-29 912.8 11 103.9 51 18.97 91 4.855

-28 858.2 12 99.02 52 18.26 92 4.705

-27 807.3 13 94.44 53 17.59 93 4.566

-26 759.7 14 90.11 54 16.94 94 4.431

-25 715.3 15 86.00 55 16.32 95 4.301

-24 673.6 16 82.09 56 15.73 96 4.176

-23 634.7 17 78.38 57 15.16 97 4.055

-22 598.2 18 74.87 58 14.62 98 3.938

-21 564.1 19 71.53 59 14.10 99 3.825

-20 532.2 20 68.36 60 13.60 100 3.716

-19 502.2 21 65.34 61 13.12 101 3.613

-18 474.1 22 62.47 62 12.65 102 3.514

-17 447.7 23 59.75 63 12.22 103 3.418

-16 423.0 24 57.17 64 11.79 104 3.326

-15 399.8 25 54.71 65 11.39 105 3.235

-14 378.0 26 52.36 66 10.99 106 3.148

-13 357.5 27 50.13 67 10.62 107 3.063

-12 338.2 28 48.01 68 10.25 108 2.982

-11 320.1 29 45.99 69 9.909 109 2.902

-10 303.1 30 44.07 70 9.576 110 2.826

-9 287.1 31 42.23 71 9.253 111 2.747

-8 272.0 32 40.48 72 8.947 112 2.672

-7 257.8 33 38.81 73 8.646 113 2.599

-6 244.4 34 37.23 74 8.362 114 2.528

-5 231.9 35 35.71 75 8.089 115 2.460

-4 220.0 36 34.27 76 7.821 116 2.390

-3 208.7 37 32.89 77 7.569 117 2.322

-2 198.2 38 31.58 78 7.323 118 2.256

-1 188.2 39 30.33 79 7.088 119 2.193

0 178.8 40 29.13 80 6.858 120 2.132

1 169.9 41 27.98 81 6.640 121 2.073

2 161.5 42 26.89 82 6.432 122 2.017

3 153.6 43 25.85 83 6.230 123 1.962

4 146.1 44 24.85 84 6.033 124 1.910

5 139.1 45 23.90 85 5.847 125 1.859

6 132.3 46 22.98 86 5.667

7 126.0 47 22.10 87 5.492

8 120.0 48 21.26 88 5.322

9 114.3 49 20.47 89 5.159

V6 VRF 50Hz

134

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3.2 Normal Operating Parameters of Refrigerant System

Under the following conditions, the operating parameters given in Tables 5-5.4 and 5-5.5 should be observed:

The master outdoor unit can detect all the indoor units.

The number of indoor units displayed on DSP2 is steady and is equal to the actual number of indoor units installed.

All stop valves are open and all indoor unit EXVs are connected to their unit’s PCB.

If the combination ratio is 100% or less, all the indoor units are currently running and if the combination ratio is more

than 100%, indoor units with total capacity equal to the total capacity of the outdoor units are currently running.

If the outdoor ambient temperature is high, the system is being run in cooling mode with the following settings:

temperature 17°C; fan speed high.

If the outdoor ambient temperature is low, the system is being run in heating mode with the following settings:

temperature 30°C; fan speed high.

The system has been running normally for more than 30 minutes.

Table 6-3.4: Outdoor unit cooling mode operating parameters

Outdoor ambient temperature °C < 10 10 to 26 26 to 31 31 to 41 > 41

Average discharge temperature °C 60-76 62-78 65-82 67-92 69-92

Average discharge superheat °C 17-30 17-33 17-34 17-36 10-32

Discharge pressure MPa 2.3-2.8 2.3-2.8 2.4-3.6 2.6-3.8 3.1-4.2

Suction pressure MPa 0.6-0.7 0.7-0.9 0.8-1.0 1.0-1.2 1.2-1.4

DC inverter compressor current A 9-20 11-22 12-25 15-29 20-26

Table 6-3.5: Outdoor unit heating mode operating parameters

Outdoor ambient temperature °C < -10 -10 to 0 0 to 5 5 to 10 10 to 17 > 17

Average discharge temperature °C 56-74 57-76 58-78 61-82 63-82 63-82

Average discharge superheat °C 17-35 17-35 17-35 17-33 14-33 14-33

Discharge pressure MPa 1.7-2.4 1.8-2.5 1.9-3.0 2.2-3.2 2.3-3.2 2.3-3.2

Suction pressure MPa 1.4-1.6 1.5-1.7 1.6-2.2 1.8-2.6 1.8-2.6 2.0-2.4

DC inverter compressor current A 11-25 13-27 12-28 11-28 11-25 15-20

Ver. 2017-12

Commercial Air Conditioner Division

Midea Group

Add.: Midea Headquarters Building, 6 Midea Avenue, Shunde, Foshan,

Guangdong, China

Postal code: 528311

Tel: +86-757-26338346

Fax: +86-757-22390205

cac.midea.com / global.midea.com

Note: Product specifications change from time to time as product improvements

and developments are released and may vary from those in this document.

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